Gluteal Tendinopathy Is Associated With Lower Patient-Reported Outcome Measures in Total Hip Arthroplasty With a Posterior Approach: A Prospective Cohort Study of 1,538 Patients.

BACKGROUND: Gluteal tendinopathy (GT) is found in 20 to 25% of patients undergoing total hip arthroplasty (THA). Despite this, there is a scarcity of literature assessing the association between GT and THA outcomes. The aim of this study was to evaluate whether intraoperative diagnosis of GT negatively affected postoperative outcomes. METHODS: Consecutive patients undergoing primary THA for osteoarthritis via a posterior approach over 5 years were recruited in a prospective study. Gluteal tendinopathy was assessed and graded at the time of surgery, but not repaired. A total of 1,538 (93%) completed the patient-reported outcome measures (PROMs) at 1 year after surgery and were included in the analysis. The PROMs included the Oxford Hip Score (OHS), Hip Disability and Osteoarthritis Outcome Score Joint Replacement (HOOS JR), and EuroQol 5-Dimension, and were collected preoperatively and one year after THA. RESULTS: The gluteal tendons were graded as 4 distinct grades: normal (n = 1,023, 66%), tendinopathy but no tear (n = 337, 22%), partial thickness tear (n = 131, 9%), and full thickness tear (n = 47, 3%). The occurrence of GT was associated with age, body mass index, and sex. There was no significant difference in baseline OHS or HOOS JR scores according to GT grade. As GT grade increased, lower median 1-year OHS (P = .001) and HOOS JR (P = .016) were observed. This association was confirmed by linear regression analysis with 1-year OHS (B = 0.5, 95% CI = -0.9 to -0.1, P = .011) when controlled for age and sex. CONCLUSIONS: Gluteal tendinopathy was commonly observed and was associated with inferior 1-year PROMs in patients undergoing THA via posterior approach. Increasing degree of tendinopathy was a negative prognostic factor for outcomes and patient satisfaction. LEVEL OF EVIDENCE: Level 2 (High quality prospective cohort study).

Foot Pain is Common, But Frequently Improves 1 Year After Total Knee Arthroplasty.

BACKGROUND: Osteoarthritis frequently affects multiple joints through the lower limbs. This study sought to examine the incidence of foot pain in subjects undergoing total knee arthroplasty (TKA) and determine if foot symptoms improved following surgery. METHODS: Six hundred ten subjects undergoing TKA completed patient-reported outcome measures preoperatively, and at 6 and/or 12 months after surgery including the incidence and severity of foot or ankle pain, Knee Injury and Osteoarthritis Outcome Scores (KOOS) Joint Replacement, Oxford Knee Scores (OKS), EQ5D, and satisfaction. RESULTS: Foot or ankle pain was reported in 45% before, 32% at 6 months, and 36% at 12 months after TKA. Of those with preoperative foot pain, 42% at 6 months and 50% at 12 months reported no foot pain after TKA, and the Visual Analog Scale severity reduced from a mean of 4.0 before to 1.7 after surgery. Those with preoperative foot pain had lower baseline KOOS (P = .001), OKS (P = .001), and more depression/anxiety (P = .010), but experienced equivalent postoperative KOOS, OKS, and satisfaction with surgery, compared to those without foot pain. CONCLUSION: Foot or ankle pain was reported by nearly half of TKA subjects, but resolved after surgery in 50%. Those with preoperative foot pain experienced at least equivalent improvement in knee-related symptoms and mobility compared to those without foot pain. The presence of foot pain should not be a deterrent to TKA.

Stable Lateral Meniscal Posterior Root Tears Left In Situ at Time of Anterior Cruciate Ligament Reconstruction Are of Minimal Long-Term Clinical Detriment.

PURPOSE: The purpose of this study was to compare long-term patient-reported outcomes in patients undergoing anterior cruciate ligament (ACL) reconstruction with untreated stable lateral meniscal posterior root (LMPR) tears to those with an intact meniscus. METHODS: Four hundred ninety-two subjects were followed for a minimum of 15-years post-ACL reconstruction and evaluated by an International Knee Documentation Committee questionnaire. The integrity of the meniscus was classified at surgery. Patients were grouped as either untreated injury to LMPR "with stable tear" (WST) group (n = 52) or intact lateral meniscus "no tear" (NT) group (n = 440). WST group included tears where those with a root avulsion within 9 mm of insertion and parrot beak tears with the integrity of the root attachment maintained. Outcomes were compared between groups. RESULTS: ACL graft rupture occurred in 10% in the WST group and in 11% in the NT group (P = .78). For participants with an intact graft (n = 440), the mean International Knee Documentation Committee scores were 82, in the WST group, and 87, in the NT group (P = .03), with a small effect size of .32. The WST group had a worse mean pain severity score (P = .04) and higher frequency of pain (P = .03) than the NT group, but the effect size was small (P < 0.3). There was no difference in the overall knee function (P = .209) or International Knee Documentation Committee activity level (P = .882). CONCLUSION: There was no adverse clinical outcome to leaving a stable LMPR tear in situ at the time of ACL reconstruction. LMPR tears left in situ were of minimal clinically significant long-term detriment, with outcomes similar to having an intact meniscus. There is an innate desire to fix the broken, but posterior meniscal root avulsions and stable parrot beak tears within 9 mm of insertion may not require intervention. At 15 years postinjury, most patients with a stable tear left in situ continue to enjoy an active lifestyle with a pain-free knee. LEVEL OF EVIDENCE: Level III, retrospective comparative study.

Improvement in Sleep Patterns After Hip and Knee Arthroplasty: A Prospective Study in 780 Patients.

BACKGROUND: This study assessed change in sleep patterns before and after total hip arthroplasty (THA) and total knee arthroplasty (TKA) and its relationship to patient-reported outcome measures (PROMs). METHODS: Between July 2016 and June 2018, surgical data and PROMs were collected on 780 subjects before and 12 months after THA or TKA. PROMs included Knee Injury and Osteoarthritis Outcome Score, Hip Disability and Osteoarthritis Outcome Score, patient satisfaction, and 2 questions from the Pittsburgh Sleep Quality Index. RESULTS: Before surgery, 35% (270 of 780) reported poor quality sleep. Sleep quality and duration were worse in females over males, and in THA patients (39%) over TKA patients (30%; P = .011). Of those reporting bad sleep, 74% (201 of 270) were improved after arthroplasty. Satisfaction was higher in subjects reporting good sleep quality (626 of 676; 93%) compared with those reporting bad sleep quality (67 of 86; 78%) (P = .001). Sleep was positively correlated with better Hip Disability and Osteoarthritis Outcome Score/Knee Injury and Osteoarthritis Outcome Score (r = 0.2-0.3). CONCLUSION: Improvement in sleep quality and duration can be expected after THA and TKA and is associated with better outcome scores and satisfaction.

Transphyseal anterior cruciate ligament reconstruction using living parental donor hamstring graft: excellent clinical results at 2 years in a cohort of 100 patients.

PURPOSE: To determine outcomes of transphyseal ACL reconstruction using a living parental hamstring tendon allograft in a consecutive series of 100 children. METHODS: One hundred consecutive juveniles undergoing ACL reconstruction with a living parental hamstring allograft were recruited prospectively and reviewed 2 years after ACL reconstruction with IKDC Knee Ligament Evaluation, and KT1000 instrumented laxity testing. Skeletally immature participants obtained annual radiographs until skeletal maturity, and long leg alignment radiographs at 2 years. Radiographic Posterior tibial slope was recorded. RESULTS: Of 100 juveniles, the median age was 14 years (range 8-16) and 68% male. At surgery, 30 juveniles were graded Tanner 1 or 2, 21 were Tanner 3 and 49 were Tanner 4 or 5. There were no cases of iatrogenic physeal injury or leg length discrepancy on long leg radiographs at 2 years, despite a median increase in height of 8 cm. Twelve patients had an ACL graft rupture and 9 had a contralateral ACL injury. Of those without further ACL injury, 82% returned to competitive sports, IKDC ligament evaluation was normal in 52% and nearly normal in 48%. The median side to side difference on manual maximum testing with the KT1000 was 2 mm (range - 1 to 5). A radiographic PTS of 12° or more was observed in 49%. CONCLUSIONS: ACL reconstruction in the juvenile with living parental hamstring tendon allograft is a viable procedure associated with excellent clinical stability, patient-reported outcomes and return to sport over 2 years. Further ACL injury to the reconstructed and the contralateral knee remains a significant risk, with identical prevalence observed between the reconstructed and contralateral ACL between 12 and 24 months after surgery. LEVEL OF EVIDENCE: III (Cohort Study).

Midterm Outcomes of Arthroscopic Reduction and Internal Fixation of Anterior Cruciate Ligament Tibial Eminence Avulsion Fractures With K-Wire Fixation.

PURPOSE: To determine the clinical and radiological outcomes of patients who underwent arthroscopic reduction and internal fixation of a tibial eminence avulsion fracture with Kirshner wires (K-wires) at a mean of 8 years following surgery. METHODS: This was a retrospective study with prospectively collected data. Inclusion criteria consisted of patients who underwent arthroscopic reduction and internal fixation of tibial eminence fracture with K-wires between 1989 and 2015 at a minimum of 18 months follow-up. Assessment included the International Knee Documentation Committee Ligament Evaluation, Lysholm Knee Score, and clinical outcomes. Magnetic resonance imaging (MRI) was performed to evaluate the anterior cruciate ligament (ACL) and evidence of osteoarthritis. RESULTS: A total of 48 participants met the inclusion criteria, and 32 were reviewed at a mean of 8 years (range, 18-260 months) after surgery. The mean age at the time of surgery was 24.5 years (10-55 years). Subsequent ACL injury occurred in 5 participants (10.4%) on the index knee and in 1 participant also on the contralateral knee; 86% had a normal examination, and no patients had >5-mm side-to-side difference on instrumented testing. The mean International Knee Documentation Committee subjective score at 8 years was 86 (range, 40-100). On MRI scan assessment for osteoarthritic changes at final follow-up, 82% of participants had no evidence of chondral wear on the medial compartment and 73% had no changes in the lateral compartment according to Magnetic Resonance Image Osteoarthritis Knee Score classification. On MRI scan qualitative assessment of ACL and tibial eminence, 7 participants (32%) were found to have high signal at the fracture site. The mean medial tibial eminence height was 9.2 mm (range, 6.3 mm to 1.31 cm) and the lateral tibial eminence height was an average of 6.7 mm (range, 0.38-0.97 mm). Significant kneeling pain was reported by 8 participants (25%). CONCLUSIONS: This study indicates that internal fixation with K-wires is an acceptable approach to reduce tibial eminence avulsion fractures, providing excellent clinical and radiological outcomes at a minimum of 18 months of follow-up. LEVEL OF EVIDENCE: Level IV, therapeutic case series.

Supercritical Carbon Dioxide-Sterilized Bone Allograft in the Treatment of Tunnel Defects in 2-Stage Revision Anterior Cruciate Ligament Reconstruction: A Histologic Evaluation.

PURPOSE: To examine the histologic properties of supercritical carbon dioxide (sCO2)-sterilized bone allograft for tunnel grafting and determine in vivo graft quality, as well as graft incorporation and remodeling, in 2-stage revision anterior cruciate ligament (ACL) surgery. METHODS: Histologic evaluation was performed in 12 subjects undergoing 2-stage revision ACL reconstruction. In the first stage, the femoral and tibial tunnels were debrided, tunnel dimensions were measured, and tunnels were grafted with sCO2-sterilized bone allograft. In the second stage, revision ACL reconstruction was performed and bone biopsy specimens were taken from the tibia. Tissue, bone, and graft volumes were measured, and histomorphometric analysis was performed. RESULTS: The mean time between the 2 stages was 8.8 months (range, 5.6-21.3 months). In the second stage, bone graft material was easily identified by its necrotic appearance comprising mature lamellar bone devoid of osteocyte nuclei within osteocyte lacunae. In all tissue samples, host-bone apposition of predominantly mature lamellar bone was noted on the surface of graft fragments in keeping with "creeping substitution." In several regions in 3 cases, osteoblastic and osteoclastic activity was evident in keeping with ongoing creeping substitution and remodeling. The mean bone volume over tissue volume was 68% (range, 33%-92%), and the mean graft volume over bone volume was 41% (range, 19%-70%). The mean graft volume (8 cases) harvested at less than 7 months (44%; 95% confidence interval, 31.4%-56.8%) was not significantly different than the mean graft volume (4 cases) harvested at greater than 10 months (34%; 95% confidence interval, 14.3%-54.2%; P = .214). CONCLUSIONS: The sCO2-sterilized bone allograft showed graft incorporation and remodeling through creeping substitution. CLINICAL RELEVANCE: The initial bone apposition and graft fragment bridging appear to provide a strong environment for ACL graft fixation resulting in technically successful 2-stage revision ACL reconstruction.

Feedback From Activity Trackers Improves Daily Step Count After Knee and Hip Arthroplasty: A Randomized Controlled Trial.

BACKGROUND: Commercial wrist-worn activity monitors have the potential to accurately assess activity levels and are being increasingly adopted in the general population. The aim of this study was to determine if feedback from a commercial activity monitor improves activity levels over the first 6 weeks after total hip arthroplasty (THA) or total knee arthroplasty (TKA). METHODS: One hundred sixty-three consecutive subjects undergoing primary TKA or THA were randomized into 2 groups. Subjects received an activity tracker with the step display obscured 2 weeks before surgery and completed patient-reported outcome measures (PROMs). On day 1 after surgery, participants were randomized to either the "feedback (FB) group" or the "no feedback (NFB) group." The FB group was able to view their daily step count and was given a daily step goal. Participants in the NFB group wore the device with the display obscured for 2 weeks after surgery, after which time they were also able to see their daily step count but did not receive a formal step goal. The mean daily steps at 1, 2, 6 weeks, and 6 months were monitored. At 6 months after surgery, subjects repeated PROMs and daily step count collection. RESULTS: Of the 163 subjects, 95 underwent THA and 68 underwent TKA. FB subjects had a significantly higher (P < .03) mean daily step count by 43% in week 1, 33% in week 2, 21% in week 6, and 17% at 6 months, compared with NFB. The FB subjects were 1.7 times more likely to achieve a mean 7000 steps per day than the NFB subjects at 6 weeks after surgery (P = .02). There was no significant difference between the groups in PROMs at 6 months. Ninety percent of FB and 83% of NFB participants reported that they were satisfied with the results of the surgery (P = .08). At 6 months after surgery, 70% of subjects had a greater mean daily step count compared with their preoperative level. CONCLUSION: Subjects who received feedback from a commercial activity tracker with a daily step goal had significantly higher activity levels after hip and knee arthroplasty over 6 weeks and 6 months, compared with subjects who did not receive feedback in a randomized controlled trial. Commercial activity trackers may be a useful and effective adjunct after arthroplasty.

Editorial Commentary: The Acrid Bioscrew in Anterior Cruciate Ligament Reconstruction of the Knee.

Bioresorbable screws have been widely adopted for graft fixation in knee anterior cruciate ligament (ACL) reconstruction on the promise of screw resorbtion and replacement by bone. When considering the value of bioresorbable screws, it is imperative to understand that the "A" in PGA and PLA, the base ingredient of all bioscrews, is for Acid. All resorb by a process of hydrolysis; the speed and extent of resorbtion is determined by both the acidity of the screw and the environment in which it is placed. Regrettably, the promise of reliable, predictable screw resorbtion and replacement by bone remains elusive, despite the addition of "osteoconductive" materials. For the most part, bioresorbables are associated with good clinical outcomes for ACL reconstruction; they are not "dangerous," just disappointing with respect to bony replacement. We propose that nonresorbing inert plastics such as PEEK (polyether ether ketone) may be better suited for the purpose of graft fixation devices for ACL reconstruction.

The Use of Routine Postoperative Microscopy and Culture Screening Following Elective Hip and Knee Arthroplasty: An Unnecessary Cost With No Effect on Clinical Management?

BACKGROUND: The use of microscopy and culture screening to detect pathogenic microorganisms followed by a decolonization protocol is a widely performed practice prior to elective hip and knee arthroplasty. In our center, the routine care of hip and knee arthroplasty also involves postoperative screening including direct culture of the surgical site. The aim of this study was to assess the frequency of pathogen detection following these tests and to determine whether routine postoperative screening, with particular reference to postoperative surgical site culture, led to any change in clinical management of these patients. METHODS: A series of 1000 patients undergoing hip or knee arthroplasty at The Mater Hospital between January 2014 and December 2015 were identified from our arthroplasty database. Results of preoperative and postoperative microscopy and culture screening were reviewed by 2 independent researchers. RESULTS: Of the 1000 subjects, positive microscopy and culture results were identified in 88 patients (8.8%) preoperatively and 5 patients (0.5%) postoperatively. None of the 1000 postoperative surgical site swabs had a positive microscopy and culture screen. All the 5 positive postoperative microscopy and culture screen results were in patients who had positive cultures preoperatively. There were no positive postoperative microscopy and culture screen results in patients who had had negative preoperative results. Postoperative screening was performed at a cost of AUS$213 per patient. CONCLUSION: Routine postoperative surgical site culture following hip and knee arthroplasty does not alter clinical management, has a significant associated financial cost, and has the potential to expose the patient to a risk of surgical site infection and is therefore not supported.

Construct Validity and Test Re-Test Reliability of the Forgotten Joint Score.

Consecutive patients undergoing knee arthroplasty completed questionnaires: FJS, Knee Injury and Osteoarthritis Outcome Score (KOOS) and WOMAC Score (mean 39 months after surgery), and were mailed a repeat questionnaire after 4 to 6 weeks. The test-retest reliability was almost perfect for the FJS (ICC = 0.97), and the FJS subdomains (ICC > 0.8). Convergent construct validity of the FJS was correlated with the KOOS Subscores of Quality of Life (0.63, P = 0.001), Symptom (0.33, P = 0.001), Pain (0.68, P = 0.001) and ADL (0.66, P = 0.001) and the Total WOMAC (0.70, P = 0.001). The FJS demonstrates high test-retest reliability and construct validity compared to the Normalised WOMAC and KOOS Subscales. The FJS does not demonstrate the ceiling effect of the WOMAC or KOOS pain scores so may have greater discriminatory ability following TKR.

A pilot study of intraoperative application of cooled radiofrequency to reduce post-operative pain following total knee arthroplasty.

BACKGROUND: Total Knee Arthroplasty (TKA) is a successful treatment for end stage knee osteoarthritis (OA), but can be associated with significant pain in the early post-operative period. Cooled radiofrequency ablation (CRFA) has reported to reduce knee OA pain by targeting the periarticular nerves. The objective of this pilot study was to assess the effectiveness of intra-operative CRFA for reducing pain and opiate use after TKA. METHODS: This was a non randomised prospective study with control group. Participants were sequentially recruited preoperatively and underwent TKA, with CRFA to 6 targeted sites prior to cementing of implants, and were compared to controls who underwent TKA without CRFA. The primary outcome was Day 3 pain scores, and secondary outcomes included week one pain scores, and opiate use up to six weeks post-operative. RESULTS: 17 participants were recruited to the control group and 12 were recruited to the CRFA group. There was no significant difference in demographics or baseline pain scores between the groups. On day 2 the CRFA group had a lower mean pain VAS score of 3.2 compared to 4.4 in the control group (p = 0.03). The mean post operative VAS pain score did not differ between the groups for Day 1, 3, 4, or any other time points up to 6 weeks. There were no significant reduction in opiate use in the CRFA group compared to the control group. There were no adverse events. CONCLUSION: This study demonstrated intra-operative CRFA was not effective in reducing pain by 50% after TKA in a pilot study.

Comparison of Contralateral ACL Rupture Versus ACL Graft Rupture in Australian Netballers After ACL Reconstruction.

Background: Netball is a popular sport worldwide, particularly for women. However, its nature puts players at high risk for anterior cruciate ligament (ACL) injury. Purpose: To determine (1) the prevalence of ACL graft rupture and contralateral ACL (CACL) rupture in Australian female netballers after ACL reconstruction (ACLR) and (2) the rate of return to sports (RTS) and psychological readiness. Study Design: Cohort study; Level of evidence, 3. Methods: A patient database identified 332 consecutive female netball players who underwent ACLR with hamstring tendon autografts performed by 2 surgeons between 2007 and 2015. Patients were retrospectively surveyed at a minimum of 7 years postoperatively-including details of a second ACL injury to either knee, RTS, and psychological readiness per the ACL-Return to Sport After Injury (ACL-RSI) score. Multivariate regression assessed the association between selected variables and repeat ACL injury. Results: A total of 267 patients (80%) were included with a mean follow-up of 8.4 years (range, 7-15 years). ACL graft rupture and CACL rupture occurred in 11 (4%) and 27 (10%) patients, respectively, at 7 years postoperatively. The ACL graft had a survival rate of 99%, 97%, 97%, and 96% at 1, 2, 5, and 7 years after surgery, respectively. The native CACL had a survival rate of 100%, 99%, 94%, and 90% at 1, 2, 5, and 7 years, respectively. Adolescents had a 4.5 times greater hazard for ACL graft rupture (95% CI, 1.4-14.6; P = .014) and a 2.5 times greater hazard for CACL rupture (95% CI, 1.2-5.5; P = .021) compared with adults. CACL injury was also associated with a return to level 1-including jumping, hard pivoting, and cutting-sports (hazard ratio, 10.3 [95% CI, 1.4-77.1]; P = .023). Most (62%) participants returned to netball, with those with higher ACL-RSI scores more likely to RTS. Conclusion: The prevalence of repeat ACL injury was higher in the contralateral knee (10%) than the ACL-reconstructed knee (4%) at 7 years postoperatively. ACLR was a suitable option for female netballers who sustained an ACL rupture with low long-term rates of graft rupture. Repeat ACL injuries to either knee were more common in adolescents and those who returned to cutting and pivoting sports.

20-Year Outcomes of High Tibial Osteotomy: Determinants of Survival and Functional Outcome.

BACKGROUND: High tibial osteotomy (HTO) is a successful joint-preserving procedure for the treatment of medial compartment osteoarthritis. Long-term survivorship of HTO ranges from 40% to 85%. There are consistent factors that predict failure. PURPOSE: To determine the 20-year survival of HTO and identify predictors of failure. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: A total of 100 consecutive patients with medial bone-on-bone arthritis were prospectively studied to provide long-term patient-reported outcome measures after lateral closing-wedge HTO and determine the time to failure. Failure was defined as conversion to arthroplasty (total knee arthroplasty or unicompartmental knee arthroplasty) or revision HTO. RESULTS: At 20 years, HTO survival was determined in 95 patients, and 5 were lost to follow-up. The overall survivorship of HTO at 20 years was 44%. The significant factors that were associated with better survivorship were age <55 years, body mass index <30, and Western Ontario and McMaster Universities Osteoarthritis Index pain score >45. These factors were used to define the favorable candidates. In the favorable candidates, survivorship was 100% at 5 years, after which there was a gradual decline to 62% survival at 20 years. Of those with HTO survival, 32 of 33 (97%) reported satisfaction with surgery, with a mean Knee injury and Osteoarthritis Outcome Score Pain score of 91 and Activities of Daily Living score of 97. CONCLUSION: HTO is a successful surgical option to treat medial compartment osteoarthritis and prevent the need for arthroplasty in young patients. The most suitable candidates for HTO are aged <55 years, are not obese, and have not progressed to severe symptomatic disability.

Outcomes of ACL Reconstruction Utilizing Supercritical CO2-Sterilized Allografts.

Background: Allograft tendons are perceived to have a high ACL graft failure rate in primary anterior cruciate ligament (ACL) reconstruction (ACLR). Historical series may be biased by graft processing methods that degrade the biomechanical properties of donor tendons such as irradiation. Supercritical carbon dioxide (SCCO2) is a validated method of terminally sterilizing biomaterials at physiological temperatures without irradiation, but in vivo use of SCCO2-processed tendon allografts for primary ACLR has not been reported to date. Hypothesis: ACLR with SCCO2 allografts would result in acceptable failure rates, subjective knee scores, and clinical evaluation at 2 years postoperatively. Study Design: Case series; Level of evidence, 4. Methods: Patients underwent primary ACLR with terminally sterilized SCCO2-processed human gracilis, peroneus longus, semitendinosus, tibialis anterior, and tibialis posterior tendon allografts. Patient demographics were collected, along with tendon donor age and sex. At 1 year postoperatively, subjective International Knee Documentation Committee (IKDC) and ACL-Return to Sport After Injury (ACL-RSI) scores were collected, as well as clinical evaluation. At 2 years postoperatively, the IKDC and ACL-RSI scores were repeated, and return to sports and further knee injuries were recorded. Results: A total of 144 patients with a medianage of 26 (IQR 14) years formed the study group. Patients were predominately male (58%). The loss to follow-up rate was 8% (n = 12). The mean age of allograft tendon donors was 37 (range 17-58) years, and the majority were male (83%). The mean allograft diameter was 8.9 ± 1.0 mm. At 2 years, ACL graft failureoccurred in 5% (n = 7). All graft failureswere in patients aged ≤25 years (P = .007). Neither donor age (≤40 or >40 years) nor donor sex was associated with graft failure (P > .05). The median IKDC subjective score was 95 and ACL-RSI score was 75. There were no revisions for sepsis within the first 2 years postoperatively. Conclusion: SCCO2 processing of allograft tendons demonstrated satisfactory clinical and patient-reported outcomes at 24 months postoperatively in a consecutive series of patients with primary ACLR, with similar ACL graft failure rates and subjective knee scores compared with those reported in published series of hamstring tendon autograft and fresh frozen nonirradiated allograft.

Randomized controlled trial of osteoconductive fixation screws for anterior cruciate ligament reconstruction: a comparison of the Calaxo and Milagro screws.

PURPOSE: To compare the outcome of 2 bioabsorbable screws for tibial interference fixation in anterior cruciate ligament reconstruction with reference to rate of absorption, osteoconductive properties, and clinical outcome. METHODS: Patients undergoing primary anterior cruciate ligament reconstruction with hamstring autograft in a single unit were invited to participate in this study. Patients were randomized to receive either the Calaxo screw (Smith & Nephew, Andover, MA) or Milagro screw (DePuy Mitek, Raynham, MA) for tibial fixation. Patients were reviewed with subjective and objective evaluation by use of the International Knee Documentation Committee form, Lysholm score, KT-1000 arthrometry (MEDmetric, San Diego, CA), and clinical examination. Magnetic resonance imaging was performed at 1 year and computed tomography scanning at 1 week and at 6, 12, and 24 months. RESULTS: Sixty patients agreed to participate in the study, with 32 patients randomized to the Calaxo screw and 28 to the Milagro screw for tibial fixation. There was no significant difference in subjective or objective clinical outcome between the 2 groups. At 24 months, 88% of Calaxo screws showed complete screw resorption compared with 0% of Milagro screws (P < .001). Tibial cysts were present in 88% of the Calaxo group and 7% of the Milagro group (P = .001). At 24 months, the mean volume of new bone formation for the Calaxo group was 21% of original screw volume. Ossification of the Milagro screw was unable to be accurately assessed as a result of incomplete screw resorption. CONCLUSIONS: Both screws showed similar favorable objective and subjective outcomes at 2 years. The Calaxo screw resorbed completely over a period of 6 months and was associated with a high incidence of intra-tunnel cyst formation. The Milagro screw increased in volume over a period of 6 months, followed by a gradual resorption, which was still ongoing at 2 years. Both screws were associated with tunnel widening, and neither showed evidence of significant tunnel ossification. We conclude that, despite satisfactory clinical outcomes, the addition of "osteoconductive" materials to bioabsorbable screws is not associated with bone formation at the screw site at 2 years. LEVEL OF EVIDENCE: Level I, randomized controlled trial.

Comparison of CT and EOS in assessing coronal lower limb alignment when planning total knee arthroplasty.

BACKGROUND: As surgical technologies and alignment strategies develop, accuracy of lower limb alignment assessment gains increasing importance. The current gold standard remains long leg (4ft) radiographs. Other measures include computed tomography (CT) and EOS scans. This study aimed to compare CT and EOS long leg views to determine the reliability of assessment of hip-knee-angle (HKA) in arthritic knees. MATERIALS AND METHODS: A retrospective study of 96 knees in patients undergoing total knee arthroplasty (TKA) was performed comparing HKA alignment data from EOS and CT. Coronal HKA and sagittal flexion angle were assessed by two independent observers. Inter-observer correlation was calculated. RESULTS: The coronal alignment on EOS was strongly positively correlated to coronal alignment on CT (r = 0.927, p = 0.001). 12 knees (13 %) exceeded CT vs EOS difference of 3°. Inter-rater reliability was excellent (intra-class coefficients >0.9). The mean difference between CT and EOS was significantly greater for patients with fixed flexion >10° (0.68) vs <10° (-0.2) p = 0.004. Mean difference in HKA did not differ between those 0-10° varus and >10° varus (p = 0.273). Valgus HKA had a higher mean difference (1.9°) compared to varus knees (-0.4°) (p = 0.001). CONCLUSION: CT and EOS showed excellent inter-rater reliability and correlated well. Increased sagittal plane deformity does effect coronal HKA assessment. Extreme varus did not affect the mean difference significantly, while valgus did. For the majority of patients either CT or EOS will give a reliable assessment of HKA but beware those with significant valgus or sagittal deformity where both modalities may be necessary to plan TKA.

Structural maturation of SYCP1-mediated meiotic chromosome synapsis by SYCE3.

In meiosis, a supramolecular protein structure, the synaptonemal complex (SC), assembles between homologous chromosomes to facilitate their recombination. Mammalian SC formation is thought to involve hierarchical zipper-like assembly of an SYCP1 protein lattice that recruits stabilizing central element (CE) proteins as it extends. Here we combine biochemical approaches with separation-of-function mutagenesis in mice to show that, rather than stabilizing the SYCP1 lattice, the CE protein SYCE3 actively remodels this structure during synapsis. We find that SYCP1 tetramers undergo conformational change into 2:1 heterotrimers on SYCE3 binding, removing their assembly interfaces and disrupting the SYCP1 lattice. SYCE3 then establishes a new lattice by its self-assembly mimicking the role of the disrupted interface in tethering together SYCP1 dimers. SYCE3 also interacts with CE complexes SYCE1-SIX6OS1 and SYCE2-TEX12, providing a mechanism for their recruitment. Thus, SYCE3 remodels the SYCP1 lattice into a CE-binding integrated SYCP1-SYCE3 lattice to achieve long-range synapsis by a mature SC.

Coiled-coil structure of meiosis protein TEX12 and conformational regulation by its C-terminal tip.

Meiosis protein TEX12 is an essential component of the synaptonemal complex (SC), which mediates homologous chromosome synapsis. It is also recruited to centrosomes in meiosis, and aberrantly in certain cancers, leading to centrosome dysfunction. Within the SC, TEX12 forms an intertwined complex with SYCE2 that undergoes fibrous assembly, driven by TEX12's C-terminal tip. However, we hitherto lack structural information regarding SYCE2-independent functions of TEX12. Here, we report X-ray crystal structures of TEX12 mutants in three distinct conformations, and utilise solution light and X-ray scattering to determine its wild-type dimeric four-helical coiled-coil structure. TEX12 undergoes conformational change upon C-terminal tip mutations, indicating that the sequence responsible for driving SYCE2-TEX12 assembly within the SC also controls the oligomeric state and conformation of isolated TEX12. Our findings provide the structural basis for SYCE2-independent roles of TEX12, including the possible regulation of SC assembly, and its known functions in meiotic centrosomes and cancer.