Introduction. Unicompartmental knee arthroplasty(UKA) has become a popular treatment alternative when one compartment of the knee is affected. Excellent intermediate results have been reported in association with the Miller-Galante unicompartmental implant. These excellent results are based on the development of the implants and the stringent patients selection. The functional cruciate ligaments has been a prerequisite for patients undergoing UKA. However, UKA can be one of the procedures in elderly patiants with deficient anterior cruciate ligaments(ACL) but with no symptoms of instability. The purpose of this report is to determine the clinical results after UKA in patients with ACL-deficient knees and compared those after UKA in ACL-intact knees. Patients and Methods. We identified 332 cases operated from May 2000 to April 2013 whose ACL were evaluated before the operation by MRI., and classified into ACL-deficient group and ACL-intact group. Fixed-bearing Miller-Galante Unicompartmental Knee System or Zimmer Unicompartmental High-Flex Knee Sytem was implanted in all patients. ACL-deficient group included 17 men and 68 women who had an average age of 79 years(range, 70–91 years) at the time of the operation. The underlying diagnosis was osteoarthritis for 77 knees and osteonecrosis for 8 knees. ACL-intact group included 49 men and 198 women who had an average age of 77 years(range, 60–88 years) at the time of the operation. The underlying diagnosis was osteoarthritis for 176 knees and osteonecrosis for 71 knees. Followup for ACL-deficient group was 3.5 years(1–8.8years), and 3.6years (1–13.2years) for ACL-intact group. Results. Japanese Orthopaedic Association score improved from 46.7points preoperatively to 76.5 points at the time of the latest followup in ACL deficient group, and 49.6 points to 81.5 points in ACL-intact group. 7 knees(8.2%) had a partial radiolucent line around the tibial component in ACL-deficient group, and 30 knees(12.6%) had a partial radiolucent line around the tibial component(30knees) or femoral component(one knee) in ACL-intact group, all of these radiolucent lines were <2mm in thickness and remained stable over time. Two knees(2.3%) in ACL-deficient group and five knees(2.0%) in ACL-intact group were revised because of progression of arthritis in the lateral tibiofemoral or patellofemoral components. All of the components in revised knees were well fixed and no polyethylene wear was seen at the time of revision. All of these results between two groups were not significantly different. Conclusion. Controversy exists about whether a functional ACL is necessary to achieve success with UKA. In classical indication, UKA should not be done in patients with symptoms of ACL instability. In elderly active patient with deficient ACL, we should prefer total knee arthroplasty. But UKA should judiciously be done in eldery patients with deficient ACL whose activity is low but with no symptoms of instability

INTRODUCION

Appropriate soft tissue balance is an important factor for postoperative function and long survival of total knee arthroplasty(TKA). Soft tissue balance is affected by ligament release, osteophyte removal, order of soft tissue release, cutting angle of tibial surface and rotational alignment of femoral components. The purpose of this study is to know the characteristics of soft tissue balance in ACL deficient osteoarthritis(OA) knee and warning points during procedures for TKA.

Background:

The aim of this study was to investigate the outcome after ACL reconstruction between a group of patients receiving a standardized supervised physiotherapy guided rehabilitation program and a group of patients who followed an un-supervised, home-based rehabilitation program.

Several studies have highlighted the relationship between anterior cruciate (ACL) injury and knee geometry particularly tibial slope (TS). However, clinical data are inconsistent, whether the lateral or medial or slopes have a different influence on ACL injury. Our goal was to assess whether the medial, lateral slopes are associated with ACL injury and whether meniscus geometry is associated with ACL injury. In addition, we sought to determine if lateral meniscal height could serve as a simple surrogate measurement for ACL injury risk. A case-controlled study compared 68 patients with an ACL injury and 68 matched nested controls. Radiological analysis of MRI measured the anterior-posterior distance of the medial and lateral plateaus, the tibial slope of both plateaus and meniscus geometry. Groups were compared using a Mann-Whitney test and α < 0 .05. The lateral tibial plateau slope was significantly higher in the ACL injured group (6.92 degrees ±5.8) versus the control group 2.68 ±5.26 (p 0.0001). In addition, the lateral meniscal slope was significantly steeper with (ACL injuries: −1 ±4.7 versus −4.73 ±4.4 (p 0.0001) in the control group. The ACL Injured group had a significantly lower lateral meniscal height 0.76 cm ±0.09, compared to the control group that has 0.88 cm ±0.12 (p 0.0001). The Lateral meniscal height had a sensitivity of 76.47% and specificity 75% for predicting ACL injury using a cut off of. Patients with ACL-injury had significantly higher lateral tibial plateau slope. Lateral meniscus height was found to be an easy measurement to make on MRI with a high specificity for predicting ACL injury. Lateral tibial slope and meniscal Geometry can be used to identify patients with high risk of an ACL injury, that might benefit from further surgery to optimize rotational stability in high-risk patients

Introduction. The knowledge of the right amount of tension of the collateral ligaments in native knees is one of the hot topics to restore the normal kinematics in TKA. To guarantee stability in TKA there should be enough tension necessary but no overtensioning. In this study we could confirm that the tension of the ligaments is not more than 20–25N on each side (in total 40–50N) to achieve stability in the knee joint. Methods and materials. During an experimental activity we examined 5 cadaveric knee specimenwith intact ligaments. With the knee in full extension, a constant force was applied on the femoral bone and the displacement was measured up a plateau was reached. This test was conducted for a knee joints with intact cruciates, then we sacrificed the anterior cruciate and in a third step the posterior cruciate even to find out if there is any change in extending the joint comparing distance and tension. Results. In all cases the tension was with intact ACL and after sacrificing it not more than 20 N (18–22N) in average, after sacrificing the PCL the tension for maximum laxity was in average 24 N (22–26N). Summary. Most devices for ligament tension work with more than 80 N to balance the knee. Especially in cases with weak ligaments or asymmetric stability can occur the problem of over- or under-tensioning to balance the knee. In our study we could show, that less tension of the ligaments are enough to stabilize the knee. Conclusion. The most important point in restoring the normal kinematics in TA is preserving the soft tissue envelope. Of course there is still the need to proceed the correct cuts to secure survivorship of TKA, but there are still 20% dissatisfied patients. We think that there is a strict correlation to the soft tissue situation, even in the tension of ligaments, capsule and muscles. Proper adaption to the normal tension situation to avoid overtensioning will improve results and show the need of measurement devices to reach this aim

The purpose of this study was to compare intra-operative, clinical, functional, and patient-reported outcomes following revision anterior cruciate ligament reconstruction (ACL-R) with a matched cohort of primary isolated ACL-R. A secondary purpose was to compare patient-reported outcomes within revision ACL-R based on intra-operative cartilage pathology. Between January 2010 and August 2017, 396 patients underwent revision ACL-R, and were matched to primary isolated ACL-R patients using sex, age, body mass index (BMI), and Beighton score. Intra-operative assessments including meniscal and chondral pathology, and graft diameter were recorded. Lachman and pivot shift tests were completed independently on each patient at two-years post-operative by a physiotherapist and orthopaedic surgeon. A battery of functional tests was assssed including single-leg Bosu balance, and four single-leg hop tests. The Anterior Cruciate Ligament-Quality of Life Questionnaire (ACL-QOL) was completed pre-operatively and two-years post-operatively. Descriptive statistics including means (M) and standard deviations (SD), and as appropriate paired t-tests were used to compare between-groups demographics, the degree and frequency of meniscal and chondral pathology, graft diameter, rate of post-operative ACL graft laxity, the surgical failure rate, and ACL-QOL scores. Comparative assessment of operative to non-operative limb performance on the functional tests was used to assess limb symmetry indices (LSI). Revision ACL-R patients were 52.3% male, mean age 30.7 years (SD=10.2), mean BMI 25.3 kg/m2 (SD=3.79), and mean Beighton score 3.52 (SD=2.51). In the revision group, meniscal (83%) and chondral pathology (57.5%) was significantly more frequent than in the primary group (68.2% and 32.1%) respectively, (p < 0 .05). Mean graft diameter (mm) in the revision ACL-R group for hamstring (M=7.89, SD=0.99), allograft (M=8.42, SD=0.82), and patellar or quadriceps tendon (M=9.56, SD=0.69) was larger than in the primary ACL-R group (M=7.54, SD=0.76, M=8.06, SD=0.55, M=9, SD=1) respectively. The presence of combined positive Lachman and pivot shift tests was significantly more frequent in the revision (21.5%) than primary group (4.89%), (p < 0 .05). Surgical failure rate was higher in the revision (10.3%) than primary group (5.9%). Seventy-three percent of revision patients completed functional testing. No significant LSI differences were demonstrated between the revision and primary ACL-R groups on any of the functional tests. No statistically significant differences were demonstrated in mean preoperative ACL-QOL scores between the revision (M=28.5/100, SD=13.5) and primary groups (M=28.5/100, SD=14.4). Mean two-year scores demonstrated statistically significant and minimally clinically important differences between the revision (M=61.1/100, SD=20.4) and primary groups (M=76.0/100, SD=18.9), (p < 0 .05). Mean two-year scores for revision patients with repair of the medial (M=59.4/100, SD=21.7) or lateral meniscus (M=59.4/100, SD=23.6), partial medial meniscectomy (M=59.7/100, SD=20), grade three or four osteoarthritis (M=55.9/100, SD=19.5), and medial femoral condyle osteoarthritis (M=59.1/100, SD=18) were lower compared with partial lateral meniscectomy (M=67.1/100, SD=19.1), grade one or two osteoarthritis (M=63.8/100, SD=18.9), and lateral femoral condyle osteoarthritis (M=62, SD=21). Revision ACL-R patients demonstrated a greater amount of meniscal and chondral pathology at the time of surgery. Two-years post-operative these patients demonstrated higher rates of graft laxity and lower ACL-QOL scores compared with the primary ACL-R group. Higher grade and medial sided osteoarthritis was associated with inferior ACL-QOL scores in revision ACL-R

The purpose of this study was to evaluate the results of selective anatomic augmentation of partial anterior cruciate (ACL) ligament tears in 36 consecutive patients with mean 3years follow-up. Our hypothesis is that this selective augmentation of partial ACL tears could restore knee stability and function. In a consecutive series of 314 ACL reconstructions, 40 patients in which intact ACL fibers remained in the location corresponding to the anteromedial or posterolateral bundle were diagnosed perioperatively. All patients underwent selective augmentation of the torn bundle, while keeping the remaining fibers intact using autogenous hamstring graft. 38 patients (28 males, 10 females) were available with minimum 3 year follow- up. 26 cases had AM bundle tears and 12 cases had PL bundle tears respectively. Patients were assessed with International Knee Documentation Committee (IKDC) 2000 Knee Evaluation Form, Lysholm score; instrumented knee testing was performed with the arthrometer (KT 2000). Statistical analysis was performed to compare the preoperative and postoperative objective evaluation. At 3 year follow-up, 12 (31.6%) patients were graded A, 25 (65.8%) graded B and 1 C (2.6%) at IKDC objective evaluation. Lysholm's score and mean side to side instrumental laxity improved significantly. The results of anatomic single bundle augmentation in partial ACL tears are encouraging with excellent side to side laxity

Purpose. The Purpose of this study was to evaluate hamstring strength after autogenous hamstring anterior cruciate ligament(ACL) reconstruction with emphasis on deeper knee flexion angles. A comparison of hamstring strength between patients undergoing ACL reconstruction using semitendinosus(ST), and those with semitendinosus and Gracilis(STG) tendons was conducted. Method. Sixty patients were prospectively followed after undergoing ACL reconstruction surgery. Forty patients received a ST graft, and 20 patients had a STG graft. All patients had standard IKDC subjective knee evaluation completed, and had bilateral hamstring strengths tested using isokinetic testing with a Cybex Orthotron machine. In addition, a hand held Microfet dynamometer was used to measure hamstring strengths at deeper knee flexion angles at six, 12, and 24 months. Results. When comparing the surgical hamstring strength compared to the control side at deeper knee flexion angle, the STG and ST group had and average of 65.0% and 79.8% strength respectively at 6 months(p<0.05). While at one year the STG and ST group had 63.6%, and 78.3% of their hamstring strength(p<0.05). Conclusion. Hamstring strength at deeper flexion angles after ACL reconstruction using autogenous semitendinosus and gracilis tendons is significantly weaker than using semitendinosus alone. The use of single tendon ACL reconstruction should be advocated to decrease morbidity of this procedure

Outcome measures are an essential element of our industry: comparing a novel procedure against an established one requires a reliable set of metrics that are comprehensible to both the technologist and the layman. We surmised that a detailed assessment of function before and after knee arthroplasty, combined with a detailed set of personal goals would enable us to test the hypothesis that less invasive joint and ligament preserving operations could be demonstrated to be more successful, and cost effective. We asked the simple question: how well can people walk following arthroplasty, and can we measure this?. Materials and methods. Using a treadmill, instrumented with force plates, we developed a regime of walking at increasing speeds and on varying inclines, both up and down hill. The data from the force plates was then extracted directly, without using the proprietary software that filtered it. Code was written in matlab script to ensure that missed steps were not mistakenly attributed to the wrong leg, automatically downloading of all the gait data at all speeds and inclines. The pattern of gait of both legs could then be compared over a range of activities. Results. Wide variation is seen in gait both before and after arthroplasty. The variables that are easiest to explain are these: . width of gait – this appears to be a pre-morbid variable, not easily correctible with surgery. (figure 1). top walking speed – total knee replacement is associated with 11% lower top speeds than uni knees or normals (p < 0.05). change in stride length with increasing speed: normal people increase their walking speed by increasing both their cadence and their stride length incrementally until a top stride length is reached. Patients with a total knee replacement do not increase their stride length at a normal rate, having to rely on increasing cadence to deliver speed increase. Patients with uni or bi-compartmental knee replacements increase speed like normal people. Downhill gait: as many as 40% of fit patients with ‘well functioning’ total knee replacements choose not to walk downhill at all, while all fit patients with ‘well functioning’ partial replacements are able to do this. Those who can manage, can only manage 90% of the normal speed, unlike unis which are indistinguishable from normal (p < 0.05). Conclusions. At higher speeds and on inclines, the presence of an intact cruciate ligament couple enables a near normal gait, following both Unicondylar knee arthroplasty and Uni + PFJ arthroplasty. Total knee arthroplasty, whether cruciate retaining or sacrificing, prevents normal gait at higher speed. An intact anterior cruciate may be an essential part of gait, playing a greater role in the swing through phase of gait. Resecting it as part of an arthroplasty may not be in the best interest of the patient's gait

Anterior cruciate ligament (ACL) reconstruction is a commonly performed operation. A variety of graft options are used with the most popular being bone-patellar-tendon-bone and hamstring autograft. There has been an increase in the popularity of hamstring autograft over the past decade. The aim of the study was to assess the ten year subjective knee function and activity level following four-strand semitendinosis and gracilis (STG) anterior cruciate ligament reconstruction. 86 patients underwent anterior cruciate reconstruction by two knee surgeons over a 12 month period (January 1999 to December 1999). 80 patients meet the inclusion criteria of arthroscopic ACL reconstruction. The same surgical technique was used by both surgeons involving four-strand STG autograft, single femoral and tibial tunnels and aperture graft fixation with the Round headed Cannulated Interference (RCI) screw. Patient evaluation was by completion of a Lysholm Knee Score and Tegner Activity Level Scale at a minimum of ten years from reconstructive surgery. This was by initial postal questionnaire and subsequent telephone follow-up. 80 patients underwent anterior cruciate reconstruction with average age 30.9 years (15 to 58 years). There was a 77.5% (62 patients) response at ten years to the questionnaire. The median Lysholm Knee Score at ten years was 94 (52 to 100). The median activity level had decreased from 9 to 5 at ten years according to the Tegner Activity Scale. 73% of patients reported a good or excellent outcome on the Lysholm score. The group of patients was further divided into those that required meniscal surgery and those that did not. The patients that did not require meniscal surgery had a median Lysholm score of 94 and those that required meniscal surgery had a similar median Lysholm score of 92.5. However it was noted that 8 patients required medial and lateral partial menisectomies at the time of original reconstruction. This group of patients had a median Lysholm Knee Score of 83.5 and Tegner Activity Scale of 4 at ten years following reconstruction. 17 of the 62 patients (27.4%) required re-operation because of further knee symptoms, with 4 patients requiring revision of the anterior cruciate following re-rupture. In conclusion anterior cruciate ligament reconstruction with four-strand STG hamstring autograft provides a reliable method of restoring knee function, with a 6% revision rate for re-rupture at ten years. Combined partial medial and lateral menisectomy at the time of the initial reconstruction is a poor prognostic indicator of function at ten years

Background. Recent publications have supported the anatomic placement of anterior cruciate grafts to optimise knee function. However, anatomic placement using the anteromedial portal has been shown to have a higher failure rate than traditional graft placement using the transtibial method. This is possibly due to it being more technically difficult and to the short femoral tunnel compromising fixation methods. It also requires the knee to be in hyper flexion. This position is not feasible during with a tourniquet in situ on the heavily muscled thighs of some athletes. Hypothesis: That navigation can be used to place the femoral tunnel in the anatomic position via a more medial transtibial tunnel. Methods. 25 patients underwent Navigated Anterior Cruciate reconstruction with quadruple hamstring grafts. The Orthopilot™ 3.0 ACL (BBraun Aesculap, Tuttlingen) software was used. The femoral and tibial ACL footprints were marked on the bones with a radio frequency probe and registered. The pivot shift test, anterior drawer and internal and external rotation were registered. A navigated tibial guide wire was inserted at 25° to the sagittal plane and 45° to the transverse plane exiting through the centre of the tibial footprint. The guide wire was advanced into the joint to just clear of the surface of the femoral footprint with the knee in 90° flexion. Flexion/extension of the knee was done to determine the closest position of the guide wire tip to the centre of the anatomical femoral footprint. If the tip was within 2mm of the centre of footprint, the position was accepted. If not the tibial guide wire was repositioned and the process repeated. The tibial tunnel was drilled, followed by transtibial drilling of the femoral tunnel. A screen shot was done to allow determination of the shape and area of the tunnel aperture relative to the femoral footprint using ImageJ (National Institute of Health). The graft was fixed proximally with an Arthrex ACL Tightrope® and distally with a Genesys™ interference screw. The pivot shift test, anterior drawer and internal and external rotation were repeated and recorded using the software. Results. In 22 out of 25 patients the centre of the drill hole was within 2mm of the centre of the anatomic femoral footprint. In 3 patients it was between 2 and 4 mm off centre. The femoral tunnel diameter ranged from 7.5mm to 9.5mm. In 23 knees there was more than 80 % overlap between the tunnel aperture and the anatomical footprint. In the other 2 knees there was 65% and 75% overlap respectively. The direction of the final tibial tunnel ranged from 22° to 28° from the sagittal plane and 42° to 49° from the transverse plane. The optimum knee flexion was between 76° and 94°. In all cases, the pivot shift recorded by the software was absent after graft fixation. There was a statistically significant difference between the anterior drawer, internal and external rotation before and after graft fixation (p<0.05). Conclusion. Based on our data, navigation allows reproducible transtibial anatomic placement of the quadruple hamstring ACL graft. This is possible when the position of the tibial tunnel is customised to the anatomy of the individual patient's knee

Background. The cruciate ligaments are important structures for biomechanical stability of the knee. For total knee arthroplasty (TKA), understanding of the exact function of the (PCL) and anterior (ACL) cruciate ligament during walking is important in the light of recent designs of bicruciate TKAs. However, studies evaluating in vivo function of the PCL during daily activities such as walking are scarce. We aimed to assess the role of the PCL during gait by measuring kinematics and kinetics of individuals with PCL deficiency and compare them with individuals with ACL deficiency and healthy young adults. Methods. Individuals with unilateral PCL deficiency (PCLD; n=9), unilateral ACL deficiency (n=10) and healthy young adults performed (n=10) 10 walk trials (5 for each leg) in which they walked over a force platform. Motion analysis (Vicon Motion Capture System) was used to calculate joint angles and internal moments around the knee, hip and ankle in the sagittal plane. Joint angles and moments of the injured knee (in PCLD and ACLD) or left knee (in HYA) were compared between groups at weight acceptance, mid-stance and push-off phases (see Fig. 1). Clinical assessment included passive knee laxity (Kneelax) for anterior (in 20–30° knee flexion) and posterior tibia translation (in 70–90° knee flexion) and Lysholm questionnaires. Results. Lysholm scores were significantly lower in PCLD and ACLD individuals compared to HYA (p's ≤ .001). PCLD subjects had more passive anterior (p = .001) and posterior tibia translation (p = .041) compared to HYA, but no significant differences were found in both directions between ACLD and HYA (p's > .10). During gait, knee angles at weight acceptance, late stance and around toe-off were not significantly different between the PCLD and HYA, and between ACLD and HYA (all p's > .06). However, the knee extension moment during mid-stance was significantly lower in the PCLD group when compared to the HYA group (p = .001; Fig. 2). Interestingly, the knee moment in the PCLD group remained positive (i.e. extension moment) throughout the stance phase, whereas HYA and ACLD groups created a substantial flexion moment around the knee at this instant. We did not observe any significant differences in hip and ankle joint angles and moments between groups. Discussion. We observed a difference in gait pattern in individuals with PCL deficiency compared to HYA, that was confined to an absence of knee flexion moments during the mid-stance phase. We hypothesize that this difference reflects a compensation strategy employed by individuals with PCL deficiency to avoid external knee (hyper)extension moments. Gait adaptations related to PCL deficiency might also have implications for design of total knee prosthesis and calls for careful evaluation of gait patterns after TKA with a specific focus on the role of the PCL. For any figures or tables, please contact the authors directly

Tendinopathy is a debilitating musculoskeletal condition which can cause significant pain and lead to complete rupture of the tendon, which often requires surgical repair. Due in part to the large spectrum of tendon pathologies, these disorders continue to be a clinical challenge. Animal models are often used in this field of research as they offer an attractive framework to examine the cascade of processes that occur throughout both tendon pathology and repair. This review discusses the structural, mechanical, and biological changes that occur throughout tendon pathology in animal models, as well as strategies for the improvement of tendon healing.

Cite this article: Bone Joint Res 2014;3:193–202.

Objectives

Surgical marking during tendon surgery is often used for technical and teaching purposes. This study investigates the effect of a gentian violet ink marker pen, a common surgical marker, on the viability of the tissue and cells of tendon.