We report on the long-term results of 163 bicruciate-retaining Hermes 2C total knee replacements in 130 patients at a mean follow-up of 22.4 years (20.3 to 23.5). Even when the anterior cruciate ligament had a partially degenerative appearance it was preserved as long as the knee had a normal anterior drawer and Lachman’s test pre-operatively. The description and surgical technique of this minimally constrained prosthesis were published in 1983 and the ten-year clinical results in 1999.

A total of 12% of the knees (20 of 163) in this study were revised because of wear of the polyethylene tibial insert. Excellent stability was achieved and the incidence of aseptic component loosening was 4.3% (seven of 163). The survival rate using revision for any reason as the endpoint was 82% (95% confidence interval 76.2 to 88.0).

Although this series included a relatively small number of replacements, it demonstrated that the anterior cruciate ligament, even when partially degenerated at the time of TKR, remained functional and provided adequate stability at a long-term follow-up.

Cite this article: Bone Joint J 2013;95-B:917–22.

Aims. The purpose of this study is to determine an individual’s age-specific prevalence of total knee arthroplasty (TKA) after cruciate ligament surgery, and to identify clinical and genetic risk factors associated with undergoing TKA. Methods. This study was a retrospective case-control study using the UK Biobank to identify individuals reporting a history of cruciate ligament surgery. Data from verbal history and procedural codes recorded through the NHS were used to identify instances of TKA. Patient clinical and genetic data were used to identify risk factors for progression from cruciate ligament surgery to TKA. Individuals without a history of cruciate ligament reconstruction were used for comparison. Results. A total of 2,576 individuals with a history of cruciate ligament surgery were identified, with 290 (11.25%) undergoing TKA. In patients with prior cruciate ligament surgery, prevalence of TKA was 0.75% at age 45 years, 9.10% at age 65 years, and 20.43% at age 80 years. Patients with prior cruciate ligament surgery were 4.6 times more likely to have undergone TKA by age 55 years than individuals without prior cruciate ligament surgery. In the cruciate ligament surgery cohort, BMI > 30 kg/m. 2. (odds ratio (OR) 4.01 (95% confidence interval (CI) 2.74 to 5.87)), a job that always involved heavy manual or physical labour (OR 2.72 (95% CI 1.57 to 4.71)), or a job that always involved walking and standing (OR 2.58 (95% CI 1.58 to 4.20)) were associated with greater TKA odds. No single-nucleotide polymorphism (SNP) was associated with risk of TKA following cruciate ligament surgery. Conclusion. Patients with a history of prior cruciate ligament surgery have substantially higher risk of TKA and undergo arthroplasty at a relatively younger age than individuals without a history of prior cruciate ligament surgery. Physically demanding work and obesity were associated with higher odds of TKA after cruciate ligament surgery, but no SNP was associated with risk of TKA. Cite this article: Bone Joint J 2024;106-B(3):249–255

To compare posterior cruciate ligament substituting (PCS) total knee arthroplasty (TKA) and posterior cruciate ligament retaining (PCR) total knee arthroplasty (TKA) to determine if greater overall flexion is obtained with the PCS TKA versus the PCR TKA at two year postoperative follow up. Secondarily, to determine whether there is a difference in the recovery of range of motion over time between the two groups from initial presentation, to discharge, and to follow up visits at three months, one year, and two years. Prospective, randomised double-blind clinical trial consisting of one hundred male and female patients scheduled for primary TKA. Sample size allows detection of a difference of six degrees of knee range of motion using two-tailed tests, =0.05, and 0.20 (80% power). SCORPIO PCL substituting total knee system and the SCORPIO PCL retaining total knee system were implanted for evaluation in this study. Patients were assessed at initial presentation, at postoperative discharge from hospital, and at follow up visits at three months, one year and two years for flexion knee range of motion. Additional data were collected utilizing the WOMAC Osteoarthritis Index, the Knee Society Clinical Rating Scale, the SF-36, and the Knee Society Radiographic Evaluation as well as data on length of stay and surgical time. Subjects were similar in demographic characteristics and all measurements at the baseline initial assessment. No differences were seen in knee flexion at two year follow up as measured using an independent t-test (p> 0.05). Recovery of knee range of motion over time was not different as measured using a two way repeated measures ANOVA (p=0.88 for group effect). Postoperative flexion and recovery of kneww range of motion was not altered following TKA by using PCS or PCR prostheses

Objectives. Congenital cruciate ligament deficiency is a rare condition that may occur in isolation or in association with longitudinal limb deficiencies such as fibular hemimelia or proximal femoral focal deficiency. Often anomalies of the menisci and their attachments can be very abnormal and impact on surgical management by standard techniques. Arthroscopic surgical knee reconstruction is undertaken to improve symptomatic instability and/or to stabilise and protect the knee for future planned limb lengthening surgery. The aim of this study is to evaluate the arthroscopic findings of patients undergoing surgery for congenital cruciate ligament deficiency, and specifically to determine the frequency and types of meniscal anatomical variations seen in these cases. Methods. Patients undergoing surgery for congenital cruciate ligament deficiency were identified from a prospectively collated database. Diagnosis was confirmed through review of the clinical notes and imaging. Operative notes and 4K saved arthroscopic images and video recordings for these cases were reviewed. Results. Over a six-year period (July 2017 – September 2023), 42 patients underwent surgery for congenital ligament deficiency and tibiofemoral instability (45 surgical episodes). Median age of patients at time of surgery was 10 years (range 4 – 17 years). The most frequent diagnosis was congenital longitudinal limb deficiency syndromes in 27 cases, with the most frequent being fibular hemimelia. Isolated congenital ligament deficiency without any other associated extra-articular manifestations occurred in 11 cases. Absence of meniscal root attachments or hypertrophy of meniscofemoral ligaments acting as ‘pseudo-cruciates’ were seen in over 25% of patients. In isolated ACL deficiency these were injured causing onset of instability symptoms and pain following trauma. Often these abnormal structures required addressing to allow surgical reconstruction. Conclusions. Our findings demonstrate that there are often meniscal variations seen in association with congenital absence or hypoplasia of the cruciate ligaments. In these patients hypertrophied meniscofemoral ligaments may act as cruciate-like structures and play a role in providing a degree of sagittal plane stability to the knee. However, when the knee becomes unstable to the point that cruciate ligament reconstruction is indicated, these meniscal variants may often require stabilisation using complex meniscal root repair techniques or variations to standard cruciate ligament reconstruction techniques to accommodate the variant anatomy

Purpose: At a time when total knee arthroplasty (TKA) with an ultra-congruent tibial plateau or a mobile plateau are advocated by many, the question is whether TKA with a fixed plateau preserving the posterior cruciate ligament (PCL) should be abandoned. We analysed the results of 500 Wallaby I TKA with preservation of the PCL and presenting asymmetrical and divergent femoral condyles with a fixed, also assymetrical tibial plateau, at mean follow-up of seven years (1–10). Material and methods: This prospective multicentric study was performed by junior and senior surgeons. Mean patient age was 70.11 years and 91.4% of the patients had primary or secondary degenerative disease. Prior surgery had been performed in 130 knees, mainly for osteotomy (n=40, mostly tibial) and revision of uni-compartmental or total prostheses (n=18). The mean preoperative IKS knee score was 26.11 points, the function score was 29.54. Preoperative alignment was correct for 11.26% of the knees, 27.16% presented > 4° valgus and 61.56% > 3° varus. Nearly all tibial and patellar pieces were cemented. 5.8% of the femoral pieces were not cemented. A prosthesis was implanted on the patella in all knees except four. There were two early infections, one popliteal sciatic paralysis and twelve wound healing problems. General mobilisation under general anaesthesia was performed in 53 knees (10.6%). Results: Twenty-two patients were not retained for analysis, fifteen lost to follow-up and seven deceased at one year. Among the 478 knees followed for one to ten years, there were six late infections (1.25%), one aseptic bipolar loosening (0.2%), 25 patellar fractures (5.23%) including three which required revision (two cerclage, one prosthesis removal), three periprosthetic femur fractures without effect on the clinical or radiographic outcome, one traumatic tear of the medial collateral ligament, and two secondary tears of the PCL without clinical consequences. There were no revisions for instability, generally considered the most frequent reason for TKA revision. The mean postoperative IKS score was 90.6 points and the function score was 59.7 points basically due to patient age and comorbidity. The eight-year survival (Kaplan-Meier method) was 98.2% (95%CI: 99.4–96.9) irrespective of the reason for revision and 99.2% (95%CI 100–98.4%) if the revision was performed for a mechanical problem. Radiographically, more than 70% of the knees were aligned (between 3° valgus and 2° varus) and more than 90% were between 5° valgus and 5° varus. Although it was difficult to measure radiographically polyethylene wear, there was only one case of > 2 mm wear with osteolysis found in 50 knees selected randomly among the knees with more than seven years follow-up. Conclusion: This study, like others reported by authors preserving the PCL, show that preservation of the PCL limits the risk of instability, allowing excellent clinical and radiographic outcome without important polyethylene wear, opening perspectives for good long-term results

Aims. The aim of this study was to assess the effect of posterior cruciate ligament (PCL) resection on flexion-extension gaps, mediolateral soft-tissue laxity, fixed flexion deformity (FFD), and limb alignment during posterior-stabilized (PS) total knee arthroplasty (TKA). Patients and Methods. This prospective study included 110 patients with symptomatic osteoarthritis of the knee undergoing primary robot-assisted PS TKA. All operations were performed by a single surgeon using a standard medial parapatellar approach. Optical motion capture technology with fixed femoral and tibial registration pins was used to assess gaps before and after PCL resection in extension and 90° knee flexion. Measurements were made after excision of the anterior cruciate ligament and prior to bone resection. There were 54 men (49.1%) and 56 women (50.9%) with a mean age of 68 years (. sd. 6.2) at the time of surgery. The mean preoperative hip-knee-ankle deformity was 4.1° varus (. sd. 3.4). Results. PCL resection increased the mean flexion gap significantly more than the extension gap in the medial (2.4 mm (. sd. 1.5) vs 1.3 mm (. sd. 1.0); p < 0.001) and lateral (3.3 mm (. sd. 1.6) vs 1.2 mm (. sd. 0.9); p < 0.01) compartments. The mean gap differences after PCL resection created significant mediolateral laxity in flexion (gap difference: 1.1 mm (. sd. 2.5); p < 0.001) but not in extension (gap difference: 0.1 mm (. sd. 2.1); p = 0.51). PCL resection significantly improved the mean FFD (6.3° (. sd. 4.4) preoperatively vs 3.1° (. sd. 1.5) postoperatively; p < 0.001). There was a strong positive correlation between the preoperative FFD and change in FFD following PCL resection (Pearson’s correlation coefficient = 0.81; p < 0.001). PCL resection did not significantly affect limb alignment (mean change in alignment: 0.2° valgus (. sd. 1.2); p = 0.60). Conclusion. PCL resection creates flexion-extension mismatch by increasing the flexion gap more than the extension gap. The increase in the lateral flexion gap is greater than the increase in the medial flexion gap, which creates mediolateral laxity in flexion. Improvements in FFD following PCL resection are dependent on the degree of deformity before PCL resection. Cite this article: Bone Joint J 2019;101-B:1230–1237

Introduction. Ideally, a patient receiving a unicondylar knee replacement will have fully functional anterior and posterior cruciate ligaments. When at least one of the cruciate ligaments is not fully functional, femoral and tibial implant contact position can potentially increase along the anterior-posterior (AP) axis. Where unicondylar implant wear testing typically uses AP resistance assuming fully functional cruciate ligaments, the authors used reduced AP resistance intended to simulate deficient cruciate ligaments. Methods. Optetrak Logic® Uni (Exactech Inc, Gainesville, FL USA) unicondylar test specimens featuring an all-UHMWPE tibial component and a cobalt chromium femoral component were used in this study. The system has a semi-constrained articular geometry. Testing was conducted at an independent testing facility (EndoLab GMBH, Thansau, Rosenheim, Germany). A four-station knee simulator was used (EndoLab knee simulator) with two unicondylar knee implants per station, giving a total of eight test specimens. Two different tibial fixation designs (keeled and peg) with identical articulating surfaces were tested. Tibial test specimens were 6 mm in thickness. Unloaded soak controls were stored in distilled water at 37°C. The test was conducted according to ISO 14243–1: 2009 [1]. Test specimens were immersed in calf serum (PAA GmBH, Cölbe, LOT B00111-5126) with a protein content of 20 g/l. Custom polyurethane molds allowed for individual component measurement. Per the ISO 14243-1, a 7% medial offset was incorporated into the set-up. The unicondylar knee implants were set at neutral position in extension. Tibial rotational restraint was 0.36 Nm/° and zero when the test specimen was within ± 6° of the reference position. This test was conducted with an AP resistance of 9.3N/mm to maximize AP displacement and simulate deficient cruciate ligaments. Typical unicondylar knee wear testing is conducted with an AP resistance of 44N/mm, which assumes functional cruciate ligaments. Results. Wear data was separated by component design (keeled and peg) as well as for medial and lateral placement [Table 1]. There was no significant difference between lateral components but there was for medial components. This difference could be due to the small sample size. Contact area of the UHMWPE tibial components was elliptical, with the longer portion along the AP axis. Mean wear rates were comparable to historical unicondylar knee systems tested at the same laboratory using the standard AP resistance (i.e., 44 N/mm). Discussion/Conclusion. This study demonstrated using an AP resistance 9.3 N/mm to simulate the presence of deficient cruciate ligaments in a unicondylar knee wear test produced similar wear rates and greater AP displacement when compared to testing using an AP resistance of 44 N/mm, which assumes functioning ligaments. This being said, design and material information about historical unicondylar knee systems tested are not known, so a direct comparison cannot be made. Performing unicondylar knee wear tests with reduced AP resistance could provide realistic wear information for devices implanted in patients without fully functioning cruciate ligaments

Poor availability of allografts in South Africa has led to an increased use of synthetic augmentation to stabilize knee joints in the treatment of knee dislocations. This study aims to evaluate multiligament knee injuries treated with a posterior cruciate ligament internal brace. The study included patients with knee dislocations who were treated with a PCL internal brace. The internal brace involved the insertion of a synthetic suture tape, which was drilled into the femoral and tibial footprint. Chronic injuries were excluded. Patient-reported outcome scores (PROMs), range of motion, stress X-Rays, and MRI scans were reviewed to assess outcomes. Acceptable outcomes were defined as a Lysholm score of 84 or more, with grade II laxity in no more than one ligament and a range of motion from full extension to 90° or more. The study included eight patients, with a median age of 42, of which five were female. None of the patients had knee flexion less than 90° or an extension deficit of more than 20°. PROMs indicated acceptable outcomes (EQ5D, Tegner Lysholm). Stress radiographs showed less than 7mm (Grade I) of posterior translation laxity in all patients. Four patients underwent MRI scans 1–2 years after the initial surgery, which revealed healing of the PCL in all patients. However, increased signal in a continuous ligament suggested only partial healing in two patients. Tunnel widening of 200% and 250% was noted around the tibial and femoral PCL footprints, respectively. All patients demonstrated stable knees and acceptable PROMs. Tunnel widening was observed in all patients who had MRI scans. Factors such as suspensory fixation, anisometric tunnel position, and the absence of PCL tear repair may have contributed to the tunnel widening

The consideration of the individual knee ligament attachments is crucial for the application of patient specific musculoskeletal models in the clinical routine, e.g. in knee arthroplasty. Commonly, the pre-operative planning is based on CT images, where no soft tissue information is available. The goal of this study was to evaluate the accuracy of a full automatic and robust mesh morphing method that estimates locations of cruciate ligament attachments on the basis of training data. The cruciate ligament attachments from 6 (n=6) different healthy male subjects (BH 184±6cm, BW 90±10kg) were identified in MRI-datasets by a clinical expert. The insertion areas were exported as point clouds and the centres of gravitation served as approximations of the attachments. These insertion points were used to annotate mean shapes of femur and tibia. The mean shapes were built up from 332 training data sets each. The surface data were obtained from CT scans by performing an automatic segmentation followed by manual cleaning steps. The mean shapes were computed by selecting a data set randomly and aligning this reference rigidly to each of the remaining data sets. The data were fitted using the non-rigid ICP variant (N-ICP-A). Due to this morphing step, point correspondences were established. By morphing a mean shape to the target geometries, including the cruciate ligament attachments, the distribution of the insertions on the original mean shape was obtained. Subsequently, a statistical mean was computed (annotated mean). The annotated mean shape was again morphed to the target data sets and the deviations of the respective predicted insertion points from the measured insertion points were computed. The training data was successfully morphed to all 6 subjects in an automatic manner with virtually no distance error (10-5 mm). The mean distance between the measured and morphed ligament attachments was highest for the ACL in the femur (4.26±1.48 mm) and lowest for PCL in the tibia (1.63±0.36 mm). The highest deviation was observed for femoral ACL (6.93 mm). In this study, a morphing based approach was presented to predict origins and insertions of the knee ligaments on the basis of CT-data, exemplarily shown for the cruciate ligaments. It has been demonstrated, that the N-ICP-A is applicable to predict the attachments automatic and robust with a high accuracy. This might help to improve patient-specific biomechanical models and their integration in the clinical routine

Aims. Total knee arthroplasty (TKA) with a highly congruent condylar-stabilized (CS) articulation may be advantageous due to increased stability versus cruciate-retaining (CR) designs, while mitigating the limitations of a posterior-stabilized construct. The aim was to assess ten-year implant survival and functional outcomes of a cemented single-radius TKA with a CS insert, performed without posterior cruciate ligament sacrifice. Methods. This retrospective cohort study included consecutive patients undergoing TKA at a specialist centre in the UK between November 2010 and December 2012. Data were collected using a bespoke electronic database and cross-referenced with national arthroplasty audit data, with variables including: preoperative characteristics, intraoperative factors, complications, and mortality status. Patient-reported outcome measures (PROMs) were collected by a specialist research team at ten years post-surgery. There were 536 TKAs, of which 308/536 (57.5%) were in female patients. The mean age was 69.0 years (95% CI 45.0 to 88.0), the mean BMI was 32.2 kg/m. 2. (95% CI 18.9 to 50.2), and 387/536 (72.2%) survived to ten years. There were four revisions (0.7%): two deep infections (requiring debridement and implant retention), one aseptic loosening, and one haemosiderosis. Results. Kaplan-Meier analysis demonstrated no difference in implant survival according to sex, age, or obesity status. Ten-year PROMs were available for 196/387 (50.6%) surviving patients and were excellent: mean Oxford Knee Score 34.4 (95% CI 32.7 to 36.1); mean Forgotten Joint Score (FJS) 51.2 (95% CI 16.1 to 86.3); mean EuroQol five-dimension five-level questionnaire score 69.9 (95% CI 46.8 to 93.0); 141/196 (71.9%) achieved the 22-point FJS patient-acceptable symptom state (PASS); and 156/196 (79.6%) were “very satisfied or satisfied”. Conclusion. This is the only large study reporting ten-year implant survival and functional outcomes of TKA using a cemented single-radius design and with a CS tibial bearing construct. The findings of excellent implant survival, safety, and functional outcomes indicate that this combination is a safe and effective option in routine TKA. Further investigation of this single-radius design TKA with CS tibial bearings with well-matched patient study groups will allow further insight into the performance of these implants. Cite this article: Bone Joint J 2024;106-B(8):808–816

Abstract. Cranial cruciate ligament (CrCL) disease/rupture causes pain and osteoarthritis (OA) in dogs. α-amino-3-hydroxy-5-methyl-4-isoxazole propionate (AMPA)-2 and kainate (KA)-1 glutamate receptors (GluR) and the excitatory amino acid transporter-1 (EAAT-1) and EAAT-3 are expressed in joint tissues from OA patients and rodent arthritis models and represent potential therapeutic targets. Objectives. To evaluate glutamate signalling in canine diseased and normal CrCL and meniscus by immunohistochemistry (IHC). Methods. Surgical waste (CrCL, n=5 and medial meniscus, n=3) were obtained from canines with CrCL disease (RCVS ethics approval:2017/14/Alves) and normal analogous tissues (n=2). IHC optimization was performed for rabbit polyclonal (AMPA-2:ab52176, KA-1:ab67402, EAAT-1:ab416) and monoclonal (EAAT-3:ab124802) antibodies from Abcam. IHC was optimised over antibody dilutions from 1:100 to 1:5000 alongside equivalent IgG isotype controls (ab37415 and ab172730) and negative controls (TBS/Tween buffer without primary antibodies). IHC staining was compared in diseased and normal tissues and disclosed with 3,3’-Diaminobenzidine (DAB). Results. Specific immunostaining was observed for all primary antibodies, at concentrations between 2.0×10. −4. mg/mL to 1.0×10. −2. mg/mL, depending on the tissue and primary antibody. All GluR and transporters were expressed in the cellular membrane, in the normal and diseased CrCL and meniscus. Healthy CrCL showed a well-organized microstructure, with normal positively labelled ligamentocytes, whereas diseased CrCL microstructure was disrupted, with many positively stained fibroblastic cells in the epiligamentous region and evident neovascularization, indicative of ongoing repair. The normal and diseased meniscal tissues showed similar chondrocytes-like cells labelling and microstructure. Negative controls demonstrated no labelling. Conclusions. GluR and transporters expression is altered in canine diseased CrCLs, implicating glutamate signalling in this pathology. Since AMPA/KA GluR antagonists alleviate joint degeneration in post-traumatic OA in rodent models, they may be useful for the treatment of CrCL disease in dogs, as well as translated to other veterinary and human orthopaedic diseases

Purpose: Injury of both cruciate ligaments raises difficult therapeutic problems in trauma victims. The severity of such lesions is related to the context of multiple trauma and to the general regional context associating vascular and neurological injury. Therapeutic management should be multidisciplinary to determine the appropriate strategy. Orthopaedic treatment should take into account the different diagnostic and therapeutic aspects. The purpose of this work was to detail ligament injuries observed and to assess results of treatments proposed. Material and methods: This retrospective series included 20 patients (14 men and 6 women), mean age 33 years (18–54). Five had multiple trauma with head injuries and multiple fractures. The initial diagnosis was traumatic knee dislocation in 14 patients. Seven patients underwent emergency vascular explorations with subsequent femoropopliteal bypass (n=3). Neurological lesions included three cases of complete section of the lateral popliteal sciatic. Orthopaedic treatment was used in three cases. We used external fixation for two months on the average in three patients. Six others underwent surgery (less than eight days after injury) after obtaining an MRI. The surgical strategy was based on several arguments: age, general status, level of the ligament injury. Three patients underwent secondary surgery on the anterior cruciate ligament. Outcome was assessed at a mean follow-up of 36 months (20–60). The clinical assessment of the objective result was based on frontal and sagittal laxity. The subjective result and the level of sports activities were also recorded. Radiographically, we studied the standard x-rays in single leg stance and also the stress images using telos with anterior then posterior drawer. Results: Excepting one case of amputation necessary due to the vascular and nervous injuries, orthopaedic treatment allowed an acceptable functional result in sedentary patients: good frontal stability and minimal anteroposterior residual laxity. Fourteen athletes underwent emergency surgery to repair the posterior cruciate ligament: posterior approaches in eight knees with injury of the floor with no posterior drawer at last follow-up; anterior approaches in six knees for suture of the posterior cruciate ligament and insertion of a synthetic ligament tutor with anterior cruciate ligament repair during the same operative time (two floor reinsertions, one patellar tendon plasty, and three Cho plasties). The stability of the posterior pivot was excellent but the tibial reinsertions of the anterior cruciate ligament failed. Seven knees required mobilisation under general anaesthesia 2.5 months later. Three knees underwent secondary anterior cruciate repair using the Kenneth Jones technique with negative Lachmann at last follow-up. Discussion: Excepting vascular and neurological emergencies dictating the initial therapeutic attitude, our orthopaedic management was based on a detailed identification of the lesion using emergency MRI: anterior or posterior approach, anterior cruciate repair technique dependng on association with peripheral ligament injury. Good results in terms of posterior laxity were achieved in this series, confirming the importance of emergency repair of the posterior cruciate. If the medial ligaments are intact, the anterior cruciate can be repaired in the emergency setting with a Cho plasy. In other situations, we prefer waiting before surgical repair of the anterior pivot

Aim: The purpose of study was to analyse osseous changes of tibial spine in radiographs of knees with aplasia of cruciate ligament. Methods: 13 patients with aplasia of cruciate ligament and respective x-rays were examined and analysed. Diagnosis were proofen by MRI or Arthroscopy. Moreover we checked patients with anterior and complete aplasia of cruciate ligament (s) separately. Results: We found typical signs of hypolasia and aplasia of intercondylar eminence in radiagraphs which correlate with anterior or complete aplasia of cruciate ligaments. These changes we classiþed in 3 types. Conclusion: Using this classiþcation it is possible to get a strong indication for aplasia of cruciate ligament only on the basis of x-rays

We have examined the relationship between the size of the flexion gap and the anterior translation of the tibia in flexion during implantation of a posterior cruciate ligament (PCL)-retaining BalanSys total knee replacement (TKR). In 91 knees, the flexion gap and anterior tibial translation were measured intra-operatively using a custom-made, flexible tensor-spacer device. The results showed that for each increase of 1 mm in the flexion gap in the tensed knee a mean anterior tibial translation of 1.25 mm (SD 0.79, 95% confidence interval 1.13 to 1.37) was produced. When implanting a PCL-retaining TKR the surgeon should be aware that the tibiofemoral contact point is related to the choice of thickness of the polyethylene insert. An additional thickness of polyethylene insert of 2 mm results in an approximate increase in tibial anterior translation of 2.5 mm while the flexed knee is distracted with a force of between 100 N and 200 N

Background:. For the past four decades controversy surrounds the decision to retain or sacrifice the posterior cruciate ligament during a total knee arthroplasty. To our knowledge no study has been done to describe the effect of releasing the PCL on the range of motion of the knee. Study design:. Case series. Methods:. Computer navigation data (Brainlab) was obtained intra-operatively from thirty patients at total knee arthroplasty. Coronal alignment, maximal passive knee extension and maximal passive flexion was captured before and after release of the PCL. Results:. Releasing the posterior cruciate ligament led to an increase in maximal extension in all patients (av 3,6°) and a decrease in coronal deformity in 63%. The surprising finding was an increase in maximal knee flexion (av 5°, range 0 to 10°.) The increase in maximal flexion was statistically significant. Conclusion:. Sacrificing the posterior cruciate ligament alters the kinematics of the knee and the resultant increase in knee flexion might explain why cruciate sacrificing total knee arthroplasty has superior flexion compared to cruciate retaining designs

The significance of the posterior cruciate ligament in the stability of the knee was investigated in dogs and it was compared with that of the anterior cruciate ligament by studying the changes produced in the knee after transection of either ligament. Osteophyte formation and changes in articular cartilage were less prominent after division of the posterior cruciate ligament. A complete longitudinal tear of the medial meniscus was found in eight out of the 10 dogs who had undergone section of the anterior cruciate but in none of the 10 with section of the posterior cruciate. It appears that, in dogs at least, the posterior cruciate ligament is less important than the anterior in the stability of the knee

In 30 rabbits, the medial meniscus was used to replace the anterior or posterior cruciate ligament. The changes that took place were followed in histological sections, obtained both from the area of insertion into bone and from the intra-articular part of the graft. There was a gradual differentiation to chondroid tissue, with subsequent calcific deposition and no appearance of normal ligamentous tissue. The strength of the graft after 52 weeks was only one-quarter of that of the normal ligament. Our results do not justify the use of the meniscus to replace a torn cruciate ligament

An operation using either the medial or the lateral meniscus to effect the late repair of torn cruciate ligaments is described. Forty-three patients under fifty years of age who were unable to return to their work because of severe joint laxity have been treated in this way and reviewed after one to thirty years. Sagittal stability was measured by a special apparatus, and a comparison was made between normal knees and affected knees before and after operation. The review of forty-five knees showed normal stability in thirty-one, slight instability in twelve and no improvement in two. Forty-one patients had returned to their former work: twenty-two complained of instability when tired; all had pain-free joints. The use of a meniscus for the reconstruction of either cruciate ligament is considered to be simple, safe and effective

We investigated the role of a functional brace worn for four months in the treatment of patients with an acute isolated tear of the posterior cruciate ligament to determine whether reduction of the posterior tibial translation during the healing period would give an improved final position of the tibia. The initial and follow-up stability was tested by Rolimeter arthrometry and radiography. The clinical outcome was evaluated using the Lysholm score, the Tegner score and the International Knee Documentation Committee scoring system at follow-up at one and two years. In all, 21 patients were studied, 21 of whom had completed one-year and 17 a two-year follow-up. The initial mean posterior sag (Rolimeter measurement) of 7.1 mm (5 to 10) was significantly reduced after 12 months to a mean of 2.3 mm (0 to 6, p < 0.001) and to a mean of 3.2 mm (2 to 7, p = 0.001) after 24 months. Radiological measurement gave similar results. The mean pre-injury Lysholm score was normal at 98 (95 to 100). At follow-up, a slight decrease in the mean values was observed to 94.0 (79 to 100, p = 0.001) at one year and 94.0 (88 to 100, p = 0.027, at two years). We concluded that the posterior cruciate ligament has an intrinsic healing capacity and, if the posteriorly translated tibia is reduced to a physiological position, it can heal with less attentuation. The applied treatment produces a good to excellent functional result

The issue of preservation or sacrifice of the posterior cruciate ligament in total knee arthroplasty remains unresolved. We report the results of 200 consecutive total knee arthroplasties performed at our hospital under the direction of the senior author. Pre-operatively, patients were randomly chosen to receive either a Kinemax (posterior cruciate retaining) or a Press-Fit-Condylar (posterior cruciate sacrificing) prosthesis. We implanted 97 Kinemax and 103 Press-Fit-Condylar prostheses which were prospectively followed-up by clinical and radiographic assessment. Review at mean follow-up of 2.7 years showed a satisfactory clinical result in both groups [Surace, et al., 1994]. We present the results of our further review, with maximum follow-up of over nine years (mean: 5.9 years). Revision of the implant has been performed in five knees (three Kinemax and two Press-Fit-Condylar). The polythene spacer had to be replaced in one patient with a Press-Fit-Condylar implant. Patients were assessed with the Hospital for Special Surgery Knee Score and radiologically assessed with the Knee Society Roentgenographic Evaluation and Scoring System. Pre-operative demographics and disease states of the patients were similar, with an average Hospital for Special Surgery Knee Score of 63. At the latest assessment the average knee score was good (85). Remarkably, the mean knee score for the posterior cruciate sacrifice and the PCL groups remains similar (mean: 85). Radiographic evaluation demonstrated that the prosthetic components of both groups were in comparable alignment. The posterior cruciate ligament retained (Kinemax) patient group showed a mean 5.9 degrees of the valgus angle at the knee. The angle in the posterior cruciate ligament sacrifice (PFC implant) group was 6.2 degrees. Evaluation of the radiolucent depths below the femoral, tibial and any patella component showed a mean total depth of 1.5 mm (pcl retaining) and 1.7 mm (pcl sacrificing). Our study presents a quantitative perspective of the results of total knee replacement with proven implant systems and performed in a general orthopaedic unit by both consultants and surgeons in training. The Kinemax (Howmedica) and Press-Fit-Condylar (DePuy Johnson and Johnson) implant systems have both previously demonstrated good results and continue to be available with little subsequent modification. To our knowledge, there have been no other large prospectively randomised studies of posterior cruciate ligament preservation or sacrifice in total knee replacement