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

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

Aims. Options for the treatment of intra-articular ligament injuries are limited, and insufficient ligament reconstruction can cause painful joint instability, loss of function, and progressive development of degenerative arthritis. This study aimed to assess the capability of a biologically enhanced matrix material for ligament reconstruction to withstand tensile forces within the joint and enhance ligament regeneration needed to regain joint function. Materials and Methods. A total of 18 New Zealand rabbits underwent bilateral anterior cruciate ligament reconstruction by autograft, FiberTape, or FiberTape-augmented autograft. Primary outcomes were biomechanical assessment (n = 17), microCT (µCT) assessment (n = 12), histological evaluation (n = 12), and quantitative polymerase chain reaction (qPCR) analysis (n = 6). Results. At eight weeks, FiberTape alone or FiberTape-augmented autograft demonstrated increased biomechanical stability compared with autograft regarding ultimate load to failure (p = 0.035), elongation (p = 0.006), and energy absorption (p = 0.022). FiberTape-grafted samples also demonstrated increased bone mineral density in the bone tunnel (p = 0.039). Histological evaluation showed integration of all grafts in the bone tunnels by new bone formation, and limited signs of inflammation overall. A lack of prolonged inflammation in all samples was confirmed by quantification of inflammation biomarkers. However, no regeneration of ligament-like tissue was observed along the suture tape materials. Except for one autograft failure, no adverse events were detected. Conclusion. Our results indicate that FiberTape increases the biomechanical performance of intra-articular ligament reconstructions in a verified rabbit model at eight weeks. Within this period, FiberTape did not adversely affect bone tunnel healing or invoke a prolonged elevation in inflammation. Cite this article: Bone Joint J 2019;101-B:1238–1247

Aims. A significant percentage of patients remain dissatisfied after total knee arthroplasty (TKA). The aim of this study was to determine whether the sequential addition of accelerometer-based navigation for femoral component preparation and sensor-guided ligament balancing improved complication rates, radiological alignment, or patient-reported outcomes (PROMs) compared with a historical control group using conventional instrumentation. Methods. This retrospective cohort study included 371 TKAs performed by a single surgeon sequentially. A historical control group, with the use of intramedullary guides for distal femoral resection and surgeon-guided ligament balancing, was compared with a group using accelerometer-based navigation for distal femoral resection and surgeon-guided balancing (group 1), and one using navigated femoral resection and sensor-guided balancing (group 2). Primary outcome measures were Patient-Reported Outcomes Measurement Information System (PROMIS) and Knee injury and Osteoarthritis Outcome (KOOS) scores measured preoperatively and at six weeks and 12 months postoperatively. The position of the components and the mechanical axis of the limb were measured postoperatively. The postoperative range of motion (ROM), haematocrit change, and complications were also recorded. Results. There were 194 patients in the control group, 103 in group 1, and 74 in group 2. There were no significant differences in baseline demographics between the groups. Patients in group 2 had significantly higher baseline mental health subscores than control and group 1 patients (53.2 vs 50.2 vs 50.2, p = 0.041). There were no significant differences in any PROMs at six weeks or 12 months postoperatively (p > 0.05). There was no difference in the rate of manipulation under anaesthesia (MUA), complication rates, postoperative ROM, or blood loss. There were fewer mechanical axis outliers in groups 1 and 2 (25.2%, 14.9% respectively) versus control (28.4%), but this was not statistically significant (p = 0.10). Conclusion. The sequential addition of navigation of the distal femoral cut and sensor-guided ligament balancing did not improve short-term PROMs, radiological outcomes, or complication rates compared with conventional techniques. The costs of these added technologies may not be justified. Cite this article: Bone Joint J 2020;102-B(6 Supple A):24–30

There have been differing descriptions of the anterolateral structures of the knee, and not all have been named or described clearly. The aim of this study was to provide a clear anatomical interpretation of these structures. We dissected 40 fresh-frozen cadaveric knees to view the relevant anatomy and identified a consistent structure in 33 knees (83%); we termed this the anterolateral ligament of the knee. This structure passes antero-distally from an attachment proximal and posterior to the lateral femoral epicondyle to the margin of the lateral tibial plateau, approximately midway between Gerdy’s tubercle and the head of the fibula. The ligament is superficial to the lateral (fibular) collateral ligament proximally, from which it is distinct, and separate from the capsule of the knee. In the eight knees in which it was measured, we observed that the ligament was isometric from 0° to 60° of flexion of the knee, then slackened when the knee flexed further to 90° and was lengthened by imposing tibial internal rotation. . Cite this article: Bone Joint J 2014;96-B:325–31

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

The meniscofemoral ligaments were studied in 84 fresh-frozen knees from 49 cadavers. Combined anterior and posterior approaches were used to identify the ligaments. In total, 78 specimens (93%) contained at least one meniscofemoral ligament. The anterior meniscofemoral ligament (aMFL) was present in 62 specimens (74%), and the posterior meniscofemoral ligament (pMFL) in 58 (69%). The 42 specimens (50%) in which both ligaments were present were from a significantly younger population than that with one MFL or none (p < 0.05). Several anatomical variations were identified, including oblique fibres of the posterior cruciate ligament (PCL), which were seen in 16 specimens (19%). These were termed the ‘false pMFL’. The high incidence of MFLs and their anatomical variations should be borne in mind during arthroscopic and radiological examination of the PCL. It is important to recognise the oblique fibres of the PCL on MRI in order to avoid wrongly identifying them as either a pMFL or a tear of the lateral meniscus. The increased incidence of MFLs in younger donors suggests that they degenerate with age

We designed an experimental study to prove the existence of the popliteofibular ligament (PFL) and to define its role in providing static stability of the knee. We also examined the contribution of the lateral collateral ligament (LCL). We found this ligament to be present in all eight human cadaver knees examined. These specimens were mounted on a specially designed rig and subjected to posterior, varus and external rotational forces. We used the technique of selective sectioning of ligaments and measured the displacement with a constant force applied, before and after its division. We recorded the displacement in primary posterior translation, coupled external rotation, primary varus angulation and primary external rotation. Statistical analysis using the standard error of the mean by plotting 95% confidence intervals, was used to evaluate the results. The PFL had a significant role in preventing excessive posterior translation and varus angulation, and in restricting excessive primary and coupled external rotation. Isolated section of the belly of popliteus did not cause significant posterolateral instability of the knee. The LCL was also seen to act as a primary restraint against varus angulation and secondary restraint against external rotation and posterior displacement. Our findings showed that in knees with isolated disruption of the PFL stability was restored when it was reconstructed. However in knees in which the LCL was also disrupted, isolated reconstruction of the PFL did not restore stability

We carried out a prospective study of 71 patients who had undergone reconstruction of the anterior cruciate ligament with the ABC scaffold. Their mean age was 28 years (18 to 50). All had either sub-acute or chronic traumatic deficiency of the ligament. The mean period of follow-up was five years (four to seven). Assessment included the use of the International Knee Documentation Committee score, the modified Lysholm score, the Tegner Activity score, the Knee Injury and Osteoarthritis Outcome score and measurement with the KT-1000 arthrometer. Two patients had mild recurrent synovitis. There were no infections and no failures of the ligament. During the period of study, two patients sustained a traumatic fracture of a femoral condyle. The implants retained their integrity in both cases. All patients returned to their previous or enhanced levels of daily activity by three months after operation and 56 (79%) achieved their pre-injury level of sporting activity by six months. The patients who were competing in National level sports returned to play at one level less after operation than before. The Lysholm score showed that 58% of the patients (41) were excellent, 34% (24) good, and 8% (6) fair, with a mean post-operative score of 93. According to the International Knee Documentation Committee score, 35% of knees (25) were ‘normal’, 52% (37) ‘nearly normal’ and 13% (9) ‘abnormal’. Complete satisfaction was noted in 90% of patients (64). The development of osteoarthritis and the management of anterior cruciate deficiency associated with laxity of the medial collateral ligament remains uncertain. Our results indicate that in the medium-term, the ABC ligament scaffold is suitable and effective when early and safe return to unrestricted activities is demanded. We acknowledge the current general hostility towards reconstruction of the anterior cruciate ligament with artificial materials following reports of early failure and chronic synovitis associatiated with the production of particulate debris. We did not encounter these problems

The requirement for release of collateral ligaments to achieve a stable, balanced total knee replacement has been reported to arise in about 50% to 100% of procedures. This wide range reflects a lack of standardised quantitative indicators to determine the necessity for a release. Using recent advances in computerised navigation, we describe two navigational predictors which provide quantitative measures that can be used to identify the need for release. The first was the ability to restore the mechanical axis before any bone resection was performed and the second was the discrepancy in the measured medial and lateral joint spaces after the tibial osteotomy, but before any femoral resection. These predictors showed a significant association with the need for collateral ligament release (p < 0.001). The first predictor using the knee stress test in extension showed a sensitivity of 100% and a specificity of 98% and the second, the difference between medial and lateral gaps in millimetres, a sensitivity of 83% and a specificity of 95%. The use of the two navigational predictors meant that only ten of the 93 patients required collateral ligament release to achieve a stable, neutral knee

We present the operative technique and clinical results of concomitant reconstruction of the medial collateral ligament (MCL) and the posterior oblique ligament for medial instability of the knee using autogenous semitendinosus tendon with preservation of the tibial attachment. The semitendinosus tendon graft between the screw on the medial epicondyle and the tibial attachment of the graft was overlapped by the MCL, while the graft between the screw and the insertion of the direct head of the semimembranosus tendon was overlapped by the central arm of the posterior oblique ligament. Assessment was by stress radiograph and the Lysholm knee scoring scale. After a mean follow-up of 52.6 months (25 to 92), the medial joint opening of the knee was within 2 mm in 22 of 24 patients. The mean Lysholm score was 91.9 (80 to 100). Concomitant reconstruction of the MCL and posterior oblique ligament using autogenous semitendinosus tendon provides a good solution to medial instability

We report the results of a prospective randomised trial which assessed the role of the posterior cruciate ligament (PCL) following total knee replacement (Genesis I; Smith and Nephew, Memphis, Tennessee). Over a four-year period, 211 patients underwent total knee replacement by the senior author (TJW). They were randomised at surgery to have the PCL either retained, excised or substituted with a posterior stabilised insert. If it was not possible to retain the ligament due to soft-tissue imbalance, it was released from its tibial insertion until suitable tension was obtained. This created a fourth group, those who were intended preoperatively to have the ligament retained, but in whom it was partially released as a result of findings at the time of surgery. All patients were evaluated using the Knee Society rating system (adapted from Insall). A total of 188 patients (212 knees) was available for follow-up at a mean of 3.5 years after surgery. Preoperatively, there was a varus deformity in 191 knees (90%) and a valgus deformity in 21 (10%). There were no statistical differences in the knee or function scores or the range of movement between the excised, retained and substituted groups. There were, however, significantly worse knee and function scores in the group in whom the PCL was released (p = 0.002)

We have undertaken a randomized clinical trial comparing two methods of reconstruction of the anterior cruciate ligament in patients with chronic instability. We used an ipsilateral bone-patellar-tendon-bone autograft in 27 patients and the Ligament Advancement Reinforcement System (LARS) artificial ligament in 26. Assessment before and at two, six, 12 and 24 months after surgery, included the history, physical examination, a modified International Knee Documentation Committee (IKDC) score, the Tegner score, the Knee Injury and Osteoarthritis Outcome Score (KOOS) and instrumented laxity testing. There were no cases of reactive synovitis or of infection of the knee, and there was no difference regarding the failure rate between the two groups. The IKDC showed no significant differences between the two groups at any stage of the follow-up. The KOOS evaluation showed consistently better results in all subscales for the LARS group during the first year of follow-up. After 24 months these differences were no longer evident. Instrument-tested laxity was greater in the LARS group at all stages of follow-up, but the differences were not significant at 24 months. Our findings suggest that at follow-up at 24 months the LARS ligament seems to be a satisfactory treatment option, especially when an early return to high levels of activity is demanded

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

We report a retrospective analysis of the results of combined arthroscopically-assisted posterior cruciate ligament reconstruction and open reconstruction of the posterolateral corner in 19 patients with chronic (three or more months) symptomatic instability and pain in the knee. All the operations were performed between 1996 and 2003 and all the patients were assessed pre- and post-operatively by physical examination and by applying three different ligament rating scores. All also had weight-bearing radiographs, MR scans and an examination under anaesthesia and arthroscopy pre-operatively. The posterior cruciate ligament reconstruction was performed using an arthroscopically-assisted single anterolateral bundle technique and the posterolateral corner structures were reconstructed using an open Larson type of tenodesis. The mean follow up was 66.8 months (24 to 110). Pre-operatively, all the patients had a grade III posterior sag according to Clancy and demonstrated more than 20° of external rotation compared with the opposite normal knee on the Dial test. Post-operatively, seven patients (37%) had no residual posterior sag, 11 (58%) had a grade I posterior sag and one (5%) had a grade II posterior sag. In five patients (26%) there was persistent minimal posterolateral laxity. The Lysholm score improved from a mean of 41.2 (28 to 53) to 76.5 (57 to 100) (p = 0.0001) and the Tegner score from a mean of 2.6 (1 to 4) to 6.4 (4 to 9) (p = 0.0001). We conclude that while a combined reconstruction of chronic posterior cruciate ligament and posterolateral corner instability improves the function of the knee, it does not restore complete stability

The management of traumatic dislocation of the knee in 40 patients (41 knees) with a mean age of 26.3 years is described. They were treated by primary repair and reconstruction with autologous grafting of the anterior (ACL) and posterior cruciate ligaments (PCL) and repair injuries to the collateral ligament and soft-tissue. The ACL and PCL were reconstructed using the patellar tendon and the gracilis and semitendinosus tendons, respectively. Early mobilisation using a continuous-passive-movement machine and active exercises was started on the second day after operation. At a mean follow-up of 39 months no patient reported ‘giving way’ and all except one had good range of movement. Of the 41 knees, 21 were rated as excellent, 15 good, four fair and one poor. Early reconstruction of the cruciate ligaments and primary repair of the collateral ligaments followed by an aggressive rehabilitation programme are recommended for these young, active patients

Most injuries to the medial collateral ligament (MCL) heal well after conservative treatment. We have identified a subgroup of injuries to the deep portion of the MCL which is refractory to conservative treatment and causes persistant symptoms. They usually occur in high-level football players and may require surgical repair. We describe a consecutive series of 17 men with a mean age of 29 years (18 to 44) who were all engaged in high levels of sport. Following a minor injury to the MCL there was persistent tenderness at the site of the proximal attachment of the deep MCL. It could be precipitated by rapid external rotation at the knee by clinical testing or during sport. The mean time from injury to presentation was 23.6 weeks (10 to 79) and none of the patients had responded to conservative treatment. The surgical finding was a failure of healing of a tear of the deep MCL at its femoral origin which could be repaired. After a period of postoperative protective bracing and subsequent rehabilitation the outcome was good. All the patients returned to their sports and remained asymptomatic at a mean of 48 weeks (28 to 60) post-operatively. Recognition of this subgroup is important since the clinical features, the course of recovery and surgical requirement differ from those of most injuries to the MCL

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

A total of 22 patients with a tibial avulsion fracture involving the insertion of the posterior cruciate ligament (PCL) with grade II or III posterior laxity were reduced and fixed arthroscopically using routine anterior and double posteromedial portals. A double-strand Ethibond suture was inserted into the joint and wrapped around the PCL from anterior to posterior to secure the ligament above the avulsed bony fragment. Two tibial bone tunnels were created using the PCL reconstruction guide, aiming at the medial and lateral borders of the tibial bed. The ends of the suture were pulled out through the bone tunnels and tied over the tibial cortex between the openings of the tunnels to reduce and secure the bony fragment. Satisfactory reduction of the fracture was checked arthroscopically and radiographically. The patients were followed-up for a mean of 24.5 months (19 to 28). Bone union occurred six weeks post-operatively. At final follow-up, all patients had a negative posterior drawer test and a full range of movement. KT-1000 arthrometer examination showed that the mean post-operative side-to-side difference improved from 10.9 mm (standard deviation (. sd. ) 0.7) pre-operatively to 1.5 mm (. sd. 0.6) (p = 0.001). The mean Tegner and the International Knee Documentation Committee scores improved significantly (p = 0.001). The mean Lysholm score at final follow-up was 92.0 (85 to 96). We conclude that this technique is convenient, reliable and minimally invasive and successfully restores the stability and function of the knee. Cite this article: Bone Joint J 2015;97-B:1220–5

A 35-year-old man was seen with pain in the back of the knee. MRI showed a mass in the anterior cruciate ligament. Biopsy indicated mucoid degeneration. Arthroscopic resection of the ligament was carried out, with relief of symptoms