The Oxford unicompartmental knee replacement
(UKR) is an established treatment option in the management of symptomatic
end-stage medial compartmental osteoarthritis (MCOA), which works
well in the young and active patient. However, previous studies
have shown that it is reliable only in the presence of a functionally
intact anterior cruciate ligament (ACL). This review reports the
outcomes, at a mean of five years and a maximum of ten years, of 52
consecutive patients with a mean age of 51 years (36 to 57) who
underwent staged or simultaneous ACL reconstruction and Oxford UKR.
At the last follow-up (with one patient lost to follow-up), the
mean Oxford knee score was 41 (. sd. 6.3; 17 to 48). Two patients
required conversion to TKR: one for progression of lateral compartment osteoarthritis
and one for infection. Implant survival at five years was 93% (95%
CI 83 to 100). All but one patient reported being satisfied with
the procedure. The outcome was not significantly influenced by age,
gender, femoral or tibial tunnel placement, or whether the procedure
was undertaken at one- or two-stages. In summary, ACL reconstruction and Oxford UKR gives good results
in patients with end-stage MCOA secondary to
Abstract. Purpose. Since arthroscopic reconstruction of the anterior cruciate ligament (ACL) started, the use of peroneus longus grafts for primary ACL reconstruction (ACLR) was never thought of as there is very scant literature on it. So, our study aims to compare the functional outcome and complications in patients with ACL injury managed by ACLR with peroneus longus tendon (PLT) and hamstring tendons (HT) respectively. Materials and Methods. Patients with 16–50 years of either gender presenting with symptomatic
Most patients (95%) with fibular hemimelia have
an absent anterior cruciate ligament (ACL). The purpose of this study
was to assess the long-term outcome of such patients with respect
to pain and knee function. We performed a retrospective review of
patients with fibular hemimelia and associated
Introduction. This study explores whether subjects with bicruciate retaining TKRs (BiCR) have more normal knee biomechanics during level walking and stair ascent than subjects with posterior cruciate retaining TKRs (PCR). Due to anterior cruciate ligament (ACL) preservation, we expect BiCR subjects will not show the reduced flexion and altered muscle activation patterns characteristic of persons with TKRs. Methods. Motion and electromyography (EMG) data were collected during level walking and stair climbing for 16 BiCR subjects (4/12 m/f, 65±3 years, 30.7±7.0 BMI, 8/8 R/L), 17 PCR subjects (2/15 m/f, 65±7 years, 30.4±5.1 BMI, 7/10 R/L), and 17 elderly healthy control subjects (8/9 m/f, 55±10 years, 25.8±4.0 BMI, 10/7 R/L), using the point cluster marker set. Surface EMG electrodes were placed on the vastus medialis obliquus (VMO), rectus femoris (RF), biceps femoris (BF), and semitendinosus (ST) muscles. EMG data are reported as percent relative voluntary contraction (%RVC), normalized to the average peak EMG signals during level walking. Statistical nonparametric mapping was used for waveform analysis. Results. Both TKR groups were older, and PCR subjects had higher BMI than control subjects (p≤0.020). The BiCR group walked slower and with shorter stride lengths than controls (p≤0.012). During level walking, BiCR subjects had less knee extension and posterior tibial displacement than controls (95–98%, 96–100% gait cycle, p=0.003, 0.001). PCR subjects showed higher flexion mid-stance than controls (36–44% gait cycle, p=0.001) and more external rotation (66–69% gait cycle, p=0.003). Both TKR groups had smaller extension moment peaks (PCR 5, 59–75, 96%, BiCR 61–78, 95–97% stance, p≤0.007, 0.003) than the control group. The BiCR group had smaller adduction and external rotation moment peaks (20–24%, 10–18% stance, p=0.003, 0.001) compared with controls. During stair climbing, BiCR subjects displayed more external tibial rotation (4–16% stance), more knee abduction (36–52% stance), and a lower adduction moment peak (24–34% stance) compared to healthy controls (p≤0.005). TKR subjects from both groups showed lower flexion moment peaks than controls (PCR 24–35%, BiCR 24–28% stance, p≤0.001, 0.004). For EMG, PCR subjects had more BF activity during stair ascent versus level walking than healthy subjects (56–74% stance, p≤0.001). Discussion. BiCR and PCR showed more similarities than expected. Both had altered kinematics and kinetics compared to controls, suggesting some intrinsic extensor mechanism weakness, possibly an aftereffect of osteoarthritis. The EMG results agreed accordingly, as both TKR groups showed (non-significant) decreased quadriceps activity during stair climbing. Interestingly, PCR subjects also had more BF activity during stair than healthy controls, a trend that is common for both TKR subjects and people with
A functional anterior cruciate ligament (ACL) or posterior cruciate ligament (PCL) has been assumed to be required for patients undergoing unicompartmental knee arthroplasty (UKA). However, this assumption has not been thoroughly tested. Therefore, this study aimed to assess the biomechanical effects exerted by cruciate ligament-deficient knees with medial UKAs regarding different posterior tibial slopes. ACL- or PCL-deficient models with posterior tibial slopes of 1°, 3°, 5°, 7°, and 9° were developed and compared to intact models. The kinematics and contact stresses on the tibiofemoral joint were evaluated under gait cycle loading conditions.Aims
Methods
We assessed proprioception using threshold levels for the perception of knee movement at slow angular velocities (0.1°/s to 0.85°/s) in 20 patients with unilateral tears of the anterior cruciate ligament (ACL) and 15 age-related control subjects. Failure to detect movement was also analysed. The threshold levels of detection did not differ between the damaged and undamaged knees in the patients or between the patients and the control group. Failure to appreciate movement, however, was significantly greater in knees with ACL loss compared with the undamaged knees of patients and the control group. Our findings show a proprioceptive deficit in the absence of the ACL. Measurements of threshold levels of detection of passive movement alone are not suitable for the evaluation of proprioceptive loss in
Implantation of ultra-purified alginate (UPAL) gel is safe and effective in animal osteochondral defect models. This study aimed to examine the applicability of UPAL gel implantation to acellular therapy in humans with cartilage injury. A total of 12 patients (12 knees) with symptomatic, post-traumatic, full-thickness cartilage lesions (1.0 to 4.0 cm2) were included in this study. UPAL gel was implanted into chondral defects after performing bone marrow stimulation technique, and assessed for up to three years postoperatively. The primary outcomes were the feasibility and safety of the procedure. The secondary outcomes were self-assessed clinical scores, arthroscopic scores, tissue biopsies, and MRI-based estimations.Aims
Methods
The patient-acceptable symptom state (PASS) is a level of wellbeing, which is measured by the patient. The aim of this study was to determine if the proportion of patients who achieved an acceptable level of function (PASS) after medial unicompartmental knee arthroplasty (UKA) was different based on the status of the anterior cruciate ligament (ACL) at the time of surgery. A total of 114 patients who underwent UKA for isolated medial osteoarthritis (OA) of the knee were included in the study. Their mean age was 65 years (SD 10). No patient underwent a bilateral procedure. Those who had undergone ACL reconstruction during the previous five years were excluded. The Knee injury Osteoarthritis Outcome Score Activities of Daily Living (KOOS ADL) function score was used as the primary outcome measure with a PASS of 87.5, as described for total knee arthroplasty (TKA). Patients completed all other KOOS subscales, Lysholm score, the Western Ontario and McMaster Universities Osteoarthritis Index, and the Veterans Rand 12-item health survey score. Failure was defined as conversion to TKA.Aims
Methods
This study aims to determine the proportion of patients with end-stage knee osteoarthritis (OA) possibly suitable for partial (PKA) or combined partial knee arthroplasty (CPKA) according to patterns of full-thickness cartilage loss and anterior cruciate ligament (ACL) status. A cross-sectional analysis of 300 consecutive patients (mean age 69 years (SD 9.5, 44 to 91), mean body mass index (BMI) 30.6 (SD 5.5, 20 to 53), 178 female (59.3%)) undergoing total knee arthroplasty (TKA) for Kellgren-Lawrence grade ≥ 3 knee OA was conducted. The point of maximal tibial bone loss on preoperative lateral radiographs was determined as a percentage of the tibial diameter. At surgery, Lachman’s test and ACL status were recorded. The presence of full-thickness cartilage loss within 16 articular surface regions (two patella, eight femoral, six tibial) was recorded.Aims
Methods
Unicompartmental knee arthroplasty (UKA) has become a popular method of treating knee localized osteoarthritis (OA). Additionally, the posterior cruciate ligament (PCL) is essential to maintaining the physiological kinematics and functions of the knee joint. Considering these factors, the purpose of this study was to investigate the biomechanical effects on PCL-deficient knees in medial UKA. Computational simulations of five subject-specific models were performed for intact and PCL-deficient UKA with tibial slopes. Anteroposterior (AP) kinematics and contact stresses of the patellofemoral (PF) joint and the articular cartilage were evaluated under the deep-knee-bend condition.Aims
Methods
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). 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 (Aims
Patients and Methods
The options for treatment of the young active patient with isolated symptomatic osteoarthritis of the medial compartment and pre-existing deficiency of the anterior cruciate ligament are limited. The potential longevity of the implant and levels of activity of the patient may preclude total knee replacement, and tibial osteotomy and unicompartmental knee arthroplasty are unreliable because of the ligamentous instability. Unicompartmental knee arthroplasties tend to fail because of wear or tibial loosening resulting from eccentric loading. Therefore, we combined reconstruction of the anterior cruciate ligament with unicompartmental arthroplasty of the knee in 15 patients (ACLR group), and matched them with 15 patients who had undergone Oxford unicompartmental knee arthroplasty with an intact anterior cruciate ligament (ACLI group). The clinical and radiological data at a minimum of 2.5 years were compared for both groups. The groups were well matched for age, gender and length of follow-up and had no significant differences in their pre-operative scores. At the last follow-up, the mean outcome scores for both the ACLR and ACLI groups were high (Oxford knee scores of 46 (37 to 48) and 43 (38 to 46), respectively, objective Knee Society scores of 99 (95 to 100) and 94 (82 to 100), and functional Knee Society scores of 96 and 96 (both 85 to 100). One patient in the ACLR group needed revision to a total knee replacement because of infection. No patient in either group had radiological evidence of component loosening. The radiological study showed no difference in the pattern of tibial loading between the groups. The short-term clinical results of combined anterior cruciate ligament reconstruction and unicompartmental knee arthroplasty are excellent. The previous shortcomings of unicompartmental knee arthroplasty in the presence of deficiency of the anterior cruciate ligament appear to have been addressed with the combined procedure. This operation seems to be a viable treatment option for young active patients with symptomatic arthritis of the medial compartment, in whom the anterior cruciate ligament has been ruptured.
An evidence-based radiographic Decision Aid for meniscal-bearing
unicompartmental knee arthroplasty (UKA) has been developed and
this study investigates its performance at an independent centre. Pre-operative radiographs, including stress views, from a consecutive
cohort of 550 knees undergoing arthroplasty (UKA or total knee arthroplasty;
TKA) by a single-surgeon were assessed. Suitability for UKA was
determined using the Decision Aid, with the assessor blinded to
treatment received, and compared with actual treatment received, which
was determined by an experienced UKA surgeon based on history, examination,
radiographic assessment including stress radiographs, and intra-operative
assessment in line with the recommended indications as described
in the literature.Aims
Patients and Methods
Graft-tunnel mismatch of the bone-patellar tendon-bone
(BPTB) graft is a major concern during anatomical anterior cruciate
ligament (ACL) reconstruction if the femoral tunnel is positioned
using a far medial portal technique, as the femoral tunnel tends
to be shorter compared with that positioned using a transtibial
portal technique. This study describes an accurate method of calculating
the ideal length of bone plugs of a BPTB graft required to avoid
graft–tunnel mismatch during anatomical ACL reconstruction using
a far medial portal technique of femoral tunnel positioning. Based on data obtained intra-operatively from 60 anatomical ACL
reconstruction procedures, we calculated the length of bone plugs
required in the BPTB graft to avoid graft–tunnel mismatch. When
this was prevented in all the 60 cases, we found that the mean length
of femoral bone plug that remained in contact with the interference
screw within the femoral tunnel was 14 mm (12 to 22) and the mean
length of tibial bone plug that remained in contact with the interference
screw within the tibial tunnel was 23 mm (18 to 28). These results
were used to validate theoretical formulae developed to predict
the required length of bone plugs in BPTB graft during anatomical
ACL reconstruction using a far medial portal technique. Cite this article:
Loss of proprioception following an anterior
cruciate ligament (ACL) injury has been well documented. We evaluated
proprioception in both the injured and the uninjured limb in 25 patients
with ACL injury and in 25 healthy controls, as assessed by joint
position sense (JPS), the threshold for the detection of passive
movement (TDPM) and postural sway during single-limb stance on a
force plate. There were significant proprioceptive deficits in both ACL-deficient
and uninjured knees compared with control knees, as assessed by
the angle reproduction test (on JPS) and postural sway on single
limb stance. The degree of loss of proprioception in the ACL-deficient
knee and the unaffected contralateral knee joint in the same patient
was similar. The TDPM in the injured knee was significantly higher
than that of controls at 30° and 70° of flexion. The TDPM of the
contralateral knee joint was not significantly different from that
in controls. Based on these findings, the effect of proprioceptive training
of the contralateral uninjured knee should be explored. Cite this article:
We retrospectively reviewed the hospital records of 68 patients who had been referred with an injury to the posterolateral corner of the knee to a specialist knee surgeon between 2005 and 2009. These injuries were diagnosed based on a combination of clinical testing and imaging and arthroscopy when available. In all, 51 patients (75%) presented within 24 hours of their injury with a mean presentation at eight days (0 to 20) after the injury. A total of 63 patients (93%) had instability of the knee at presentation. There was a mean delay to the diagnosis of injury to the posterolateral corner of 30 months (0 to 420) from the time of injury. In all, the injuries in 49 patients (72%) were not identified at the time of the initial presentation, with the injury to the posterolateral corner only recognised in those patients who had severe multiple ligamentous injuries. The correct diagnosis, including injury to the posterolateral corner, had only been made in 34 patients (50%) at time of referral to a specialist knee clinic. MRI correctly identified 14 of 15 injuries when performed acutely (within 12 weeks of injury), but this was the case in only four of 15 patients in whom it was performed more than 12 weeks after the injury. Our study highlights a need for greater diligence in the examination and investigation of acute ligamentous injuries at the knee with symptoms of instability, in order to avoid failure to identify the true extent of the injury at the time when anatomical repair is most straightforward.
This prospective study describes the outcome of the first 1000 phase 3 Oxford medial unicompartmental knee replacements (UKRs) implanted using a minimally invasive surgical approach for the recommended indications by two surgeons and followed up independently. The mean follow-up was 5.6 years (1 to 11) with 547 knees having a minimum follow-up of five years. At five years their mean Oxford knee score was 41.3 ( The incidence of implant-related re-operations was 2.9%; of these 29 re-operations two were revisions requiring revision knee replacement components with stems and wedges, 17 were conversions to a primary total knee replacement, six were open reductions for dislocation of the bearing, three were secondary lateral UKRs and one was revision of a tibial component. The most common reason for further surgical intervention was progression of arthritis in the lateral compartment (0.9%), followed by dislocation of the bearing (0.6%) and revision for unexplained pain (0.6%). If all implant-related re-operations are considered failures, the ten-year survival rate was 96% (95% confidence interval, 92.5 to 99.5). If only revisions requiring revision components are considered failures the ten-year survival rate is 99.8% (confidence interval 99 to 100). This is the largest published series of UKRs implanted through a minimally invasive surgical approach and with ten-year survival data. The survival rates are similar to those obtained with a standard open approach whereas the function is better. This demonstrates the effectiveness and safety of a minimally invasive surgical approach for implanting the Oxford UKR.
A total of 218 patients with unilateral anterior cruciate ligament deficiency were randomly assigned to one of four groups. In group A an anatomical double bundle anterior cruciate ligament reconstruction was performed; group B were treated by a single bundle using an Endobutton for femoral fixation; in group C by a single bundle using RigidFix cross pins for femoral fixation; and in group D by a single bundle using a bioabsorbable TransFix II screw for femoral fixation. For tibial fixation a bioabsorbable Intrafix interference screw was used for all the groups and the graft was fashioned from the semitendinosus and gracilis tendons in all patients. In all, 18 patients were lost to follow-up. The remaining 200 were subjected to a clinical evaluation, with assessment of the anterior drawer, Lachman’s and the pivot-shift tests, and KT-1000 arthrometer measurement. They also completed the International Knee Documentation Committee, Lysholm knee and Tegner activity scores. At a mean of 29 months (25 to 38) follow-up there were no significant differences concerning time between injury and range of movement and Lysholm knee scores among the four groups. However, the double bundle method showed significantly better results for the pivot-shift test (p = 0.002). The KT 1000 measurements showed a mean difference between the reconstructed knee and the patients’ normal knee of 1.4 mm in the double bundle group and 2.4 mm in the single bundle group; which was statistically significant. The Lachman and anterior drawer tests also showed superior results for the double bundle method. The International Knee Documentation Committee scale showed no significant difference among the groups (p <
0.001). On clinical evaluation the double bundle group showed less laxity than the single bundle groups. However, regardless of the technique, all knees were improved by anterior cruciate ligament reconstruction compared with their pre-operative status.
We reviewed 87 patients who underwent revision reconstruction of the anterior cruciate ligament. The incidence of meniscal tears and degenerative change was assessed and related to the interval between failure of the primary graft and revision reconstruction. Patients were divided into two groups: early revision surgery within six months of graft failure, and delayed revision. Degenerative change was scored using the French Society of Arthroscopy system. There was a significantly higher incidence of articular cartilage degeneration in the delayed group (Mann-Whitney U-test, 53.2% We conclude that revision reconstruction should be carried out within six months of primary graft failure, in order to minimise the risk of degenerative change.
We reviewed 183 patients who had undergone reconstruction of the anterior cruciate ligament. The incidence of meniscal tears and degenerative change was assessed and related to the timing from injury to surgery. Degenerative change was scored using the French Society of Arthroscopy system. The patients were divided into an early (surgery within 12 months of injury) and a late group (surgery more than 12 months from injury). The late group was also subdivided into four groups of 12-month periods ranging from one year to more than four years after injury. There was a significantly higher incidence of meniscal tears in patients undergoing reconstruction after 12 months compared with those in the early group (71.2%