The purpose of this study was to evaluate the long-term functional and radiological outcomes of arthroscopic removal of unstable osteochondral lesions with subchondral drilling in the lateral femoral condyle. We reviewed the outcome of 23 patients (28 knees) with stage III or IV osteochondritis dissecans lesions of the lateral femoral condyle at a mean follow-up of 14 years (10 to 19). The functional clinical outcomes were assessed using the Lysholm score, which improved from a mean of 38.1 (. sd. 3.5) pre-operatively to a mean of 87.3 (. sd. 5.4) at the most recent review (p = 0.034), and the Tegner activity score, which improved from a pre-operative median of 2 (0 to 3) to a median of 5 (3 to 7) at final follow-up (p = 0.021). The radiological degenerative changes were evaluated according to Tapper and Hoover’s classification and when compared with the pre-operative findings, one knee had grade 1, 22 knees had grade 2 and five knees had grade 3 degenerative changes. The overall outcomes were assessed using Hughston’s rating scale, where 19 knees were rated as good, four as fair and five as poor. We found radiological evidence of degenerative changes in the third or fourth decade of life at a mean of 14 years after arthroscopic excision of the loose body and subchondral drilling for an unstable osteochondral lesion of the lateral femoral condyle. Clinical and functional results were more satisfactory

With medial unicompartmental osteoarthritis (OA) there is occasionally a full-thickness ulcer of the cartilage on the medial side of the lateral femoral condyle. It is not clear whether this should be considered a contraindication to unicompartmental knee replacement (UKR). The aim of this study was to determine why these ulcers occur, and whether they compromise the outcome of UKR. Case studies of knees with medial OA suggest that cartilage lesions on the medial side of the lateral condyle are caused by impingement on the lateral tibial spine as a result of the varus deformity and tibial subluxation. Following UKR the varus and the subluxation are corrected, so that impingement is prevented and the damaged part of the lateral femoral condyle is not transmitting load. An illustrative case report is presented. Out of 769 knees with OA of the medial compartment treated with the Oxford UKR, 59 (7.7%) had partial-thickness cartilage loss and 20 (2.6%) had a full-thickness cartilage deficit on the medial side of the lateral condyle. The mean Oxford Knee Score (OKS) at the last follow-up at a mean of four years was 41.9 (13 to 48) in those with partial-thickness cartilage loss and 41.0 (20 to 48) in those with full-thickness loss. In those with normal or superficially damaged cartilage the mean was 39.5 (5 to 48) and 39.7 (8 to 48), respectively. There were no statistically significant differences between the pre-operative OKS, the final review OKS or of change in the score in the various groups. We conclude that in medial compartment OA, damage to the medial side of the lateral femoral condyle is caused by impingement on the tibial spine and should not be considered a contraindication to an Oxford UKR, even if there is extensive full-thickness ulceration of the cartilage

We describe the mid-term results of a prospective study of total knee replacement in severe valgus knees using an osteotomy of the lateral femoral condyle and computer navigation. There were 15 knees with a mean valgus deformity of 21° (17° to 27°) and a mean follow-up of 28 months (24 to 60). A cemented, non-constrained fixed bearing, posterior-cruciate-retaining knee prosthesis of the same design was used in all cases (Columbus-B. Braun; Aesculap, Tuttlingen, Germany). All the knees were corrected to a mean of 0.5° of valgus (0° to 2°). Flexion of the knee had been limited to a mean of 85° (75° to 110°) pre-operatively and improved to a mean of 105° (90° to 130°) after operation. The mean Knee Society score improved from 37 (30 to 44) to 90 points (86 to 94). Osteotomy of the lateral femoral condyle combined with computer-assisted surgery gave an excellent mid-term outcome in patients undergoing total knee replacement in the presence of severe valgus deformity

We reviewed seven patients with coronal fractures of the lateral femoral condyle and studied the mechanism of injury and the radiological features. The influence of soft tissue attachments on the displacement and the blood supply were investigated by clinical and cadaveric studies. All three fractures which were initially undisplaced lost position early during conservative management. Internal fixation gave good results at review, and is recommended to avoid the risk of malunion and possible secondary osteoarthritis

Four children are described, each with spontaneous osteonecrosis affecting nearly one-third of the lateral femoral condyle. All the children had a motor and a sensory deficit in the affected limb: two had been previously treated for neuroblastoma of the spine, one for an infected lumbar dermoid cyst and one had spina bifida. We consider that these disorders, singly or in combination, may lead to repeated excessive loading of the lateral femoral condyle, which cannot be appreciated in a knee that is not protected by normal sensation

Twenty patients with an average age of eighteen and a half years sustained osteochondral fractures of the lateral femoral condyle as the result of a sudden twist and valgus strain to the straight or almost straight knee. All the patients felt sudden pain at the moment of injury, all had a haemarthrosis, and yet the fracture escaped early diagnosis in one-third of the cases. Internal fixation of the fragment with early mobilisation is recommended if the diagnosis is made within two weeks of injury, and excision of the fragment if it is only later identified

Introduction. Hoffa fractures are rare, intra-articular fractures of the femoral condyle in the coronal plane and involving the weight-bearing surface of the distal femur. Surgical fixation is warranted to achieve stability, early mobilisation and satisfactory knee function. We describe a unique type of Hoffa fracture in the coronal plane with sagittal split and intra-articular comminution. There is scant evidence in current literature with regards to surgical approaches, techniques and implants. We report of our case with a review of the literature. Case report. A 40 year old male motorcyclist was involved in a high speed road traffic collision. X-rays confirmed displaced unicondylar fracture of the lateral femoral condyle. CT showed sagittal split of the Hoffa fragment and intra-articular comminution. MRI showed partial rupture of the anterior cruciate ligament. The patient underwent definitive surgical treatment via a midline skin incision and lateral parapatellar approach using cannulated screws, headless compression screws and anti-glide plate. Weightbearing was commenced at 8 weeks. Arthroscopy and adhesiolysis was performed at 12 weeks to improve range of motion. The patient was discharged at one year with a pain-free, functional knee. Discussion. Hoffa fractures are high-energy fractures, often seen in young male motorcyclists with flexed and slightly abducted knee. Most papers recommend surgical fixation, however there is no widely accepted surgical method or rehabilitation regime. Varying surgical approaches, screw direction, choice of implants, and post-operative care have been described. Surgical approach depends on the configuration of the fracture. The medial/lateral parapatellar approach is commonly used as it does not compromise future arthroplasty, but it does not allow access to fix posterior comminution. Arthroscopic-assistance may be used with good outcomes and less tissue dissection. AP screws are widely reported in the literature, most likely due to easier access to the fracture site. PA screws may provide better stability, but access is more difficult. Fixation often involves passing screws through the articular surface, therefore the area damaged should be kept to a minimum by using the smallest possible screw; headless compression screws leave a smaller footprint in the articular cartilage. Locking plate augmentation generally gives good outcomes. Conclusion. Hoffa fractures are rare and difficult to treat. Surgical treatment is the best choice for optimum post-operative knee function. There is no consensus on choice of surgical approaches, techniques and implants, as these are dependent on fracture configuration. In this particular case we emphasise the importance of using an anti-glide plate to address the sagittal component. Despite the need for a secondary procedure, the treatment has had positive outcomes and may be used as a guide for treatment of future Hoffa fractures of a similar sub-type

Between 1995 and 2000, nine patients between the ages of 12 and 15 years were treated for very large osteochondral fractures of the lateral femoral condyle with internal fixation of the displaced osteochondral fragment with bioabsorbable pins. Initial healing in these patients has been assessed with either follow up arthroscopy or MRI scanning. Early results suggested very good healing of the detached fragments. The aim of this study was to review these patients at greater than five years follow up to assess how the healed articular cartilage has survived and performed. Eight of the nine patients were able to be followed up for clinical assessment, IKDC rating, Noyes Cincinnati Knee rating, radiologic and MRI assessment. Under the IKDC Knee Scoring system, five patients scored a final grade of A, two patients scored a grade of B and one patient scored C. Under the Noyes Cincinnati Knee Scoring system, three of the eight patients scored excellent, two scored good and three had a final rating of fair. There were no poor results. X-rays, including weight bearing views, were assessed for evidence of lateral compartment degeneration. Six patients had normal knee x-rays. Two patients had subchondral bony irregularity in the lateral compartment with subtle lateral compartment narrowing. We found that MRI scanning with specific cartilage sequences was an accurate way to assess healing and integrity of the articular cartilage at greater than 5 years. All patients had intact articular cartilage in the lateral compartment with no area of full thickness articular cartilage loss. Six of the eight patients had a small abnormal cleft-like signal corresponding to the likely posterior margin of the initial fracture fragment. Two patients had no cleft-like signal. The meniscii appeared normal in all patients. No evidence of pin tracts remained. Our five-year follow up results suggest that the majority of the reattached articular cartilage does survive and these young, active patients’ knees have functioned well. The outcome in the longer term remains guarded. We recommend that internal fixation of these fragments with bioabsorbable pins, or other appropriate means of fixation, is a worthwhile procedure

Abstract. Background. Conventional TKR aims for neutral mechanical alignment which may result in a smaller lateral distal femoral condyle resection than the implant thickness. We aim to explore the mismatch between implant thickness and bone resection using 3D planning software used for Patient Specific Instrumentation (PSI) TKR. Methods. This is a retrospective anatomical study from pre-operative MRI 3D models for PSI TKR. Cartilage mapping allowed us to recreate the native anatomy, enabling us to quantify the mismatch between the distal lateral femoral condyle resection and the implant thickness. Results. We modelled 292 knees from PSI TKR performed between 2012 and 2015. There were 225 varus knees and 67 valgus knees, with mean supine hip-knee-angle of 5.6±3.1 degrees and 3.6±4.6 degrees, respectively. In varus knees, the mean cartilage loss from medial and lateral femoral condyle was 2.3±0.7mm and 1.1±0.8mm respectively; the mean overstuffing of the lateral condyle 1.9±2.2mm. In valgus knees, the mean cartilage loss from medial and lateral condyle was 1.4±0.8mm and 1.5±0.9mm respectively; the mean overstuffing of the lateral condyle was 4.1±1.9mm. Conclusions. Neutral alignment TKR often results in overstuffing of the lateral condyle. This may increase the patello-femoral pressure at the lateral facet in flexion. Anterior knee pain may be persistent even after patellar resurfacing due to tight lateral retinacular structures. An alternative method of alignment such as anatomic alignment may minimise this problem

Abstract. Introduction. Fractures of the articular surface of the patella or the lateral femoral condyle usually occur following acute dislocation of the patella. This study looked at the radiological and functional outcomes of fixation of osteochondral fractures. Methods. Twenty-nine patients (18 male, 11 female) sustained osteochondral fractures of the knee following patellar dislocation. All patients had detailed radiographic imaging and MRI scan of the knee preoperatively. An arthroscopic assessment was done, followed by fixation using bio-absorbable pins or headless screws either arthroscopically or mini-open arthrotomy. VMO plication or MPFL repair were done if necessary. MRI scan was done at follow-up to assess for healing of the fixed fragment prior to patient discharge. Results. The mean age of the patients was 21 yrs (9–74), 11 had osteochondral fracture of the patella (38%), while 18 were from the lateral femoral condyle (62%). 13 patients needed additional VMO plication. Mean follow up period was 7.7 years (1 to 12 years). As per Tegner activity scale, all patients returned to their pre-injury activity level (Mean score 7) and sports. None of the patients had a further episode of patellar dislocation. Mean postoperative IKDC score was 86.5 (SD 17.3), Kujala was 91.1(SD 15.5) and Tegner- lysholm was 88.7 (SD 14.4). All patients had statistically significant (p < 0.05) improvement. Post-operative MRI scan showed satisfactory union in all cases (100%). Conclusion. It is extremely important to identify this group of injury and treat them early to have satisfactory knee function and avoid long term complications of arthritis

INTRODUCTION. In living normal knee the lateral femoral condyle rolls posteriorly more than the medial side to the extent that in deep flexion the lateral femoral condyle sublux from the tibial surface (Nakagawa et al). The purpose of this presentation is to study the tibiofemoral movement in patients who had full flexion after total knee replacements and to compare it with that of normal knee. MATERIALS AND METHODS. 23 knees were scanned using SIEMENS SIREMOBILE Iso-C with 3D Extension C-arm. The system is able reconstruct 3D images that can be viewed from deferent angle and precise measurements of distances between the deferent components of the implant can be made. The knee was scanned while the patient is sitting in kneeling position with the calf touching the thigh (flexion of over 150 degree). RESULTS. All the cases studied showed a variable roll back between the medial and lateral femoral condyle. In all cases the lateral roll back was much more than the medial. In 14 cases we confirmed lateral condyle subluxation similar to what is seen in normal knee. The position of the foot (internal or external rotation) during scanning did not affect the lateral femoral condyle role back. DISCUSSION. Although previous studies have shown paradoxical types of tibiofemoral movement in patients who have total knee replacements throughout the range of movement, the knees in patients who had full flexion after TKA tend to have the same tibiofemoral movement as the normal knee in deep flexion. The lateral femoral condyles spin off or subluxation could adversely affect the implant components especially if the design does not accommodate this movement. CONCLUSION. The lateral femoral condyle may sublux from the tibia during kneeling in patients who had full flexion after TKA. These findings should call for changes in the implant design to accommodate the lateral condyle roll back

Autologous osteochondral transplantation (AOT) is an effective treatment for large Osteochondral Lesions of the Talus (OLT), however little is reported on an athletic population, who are likely to place higher demands on the reconstruction. The aim is to report the outcomes of large OLT (>150mm. 2. ) within an athletic population. The study population was limited to professional or amateur athletes (Tegner score >6) with an OLT of size 150mm. 2. or greater. The surgical intervention was AOT with a donor site from the lateral femoral condyle. Clinical outcomes at a minimum of 24 months included Return to Sport, VAS and FAOS Scores. In addition, graft incorporation was evaluated by MRI using MOCART scores at 12 months post-surgery. 38 athletes including 11 professional athletes were assessed. Mean follow-up was 46 months. Mean lesion size was 249mm. 2. 33 patients returned to sport at their previous level and one did not return to sport (mean return to play 8.2 months). Visual analogue scores improved from 4.53 pre-operatively to 0.63 post-operatively (p=0.002). FAOS Scores improved significantly in all domains (p< 0.001). Two patients developed knee donor site pain, and both had three osteochondral plugs harvested. Univariant analysis demonstrated no association between pre-operative patient or lesion characteristics and ability to return to sport. However, there was a strong correlation between MOCART scores and ability to return to sport (AUC=0.89). Our study suggests that AOT is a viable option in the management of large osteochondral talar defects in an athletic population, with favourable return to sport levels, patient satisfaction, and FAOS/VAS scores. The ability to return to sport is predicated upon good graft incorporation and further research is required to optimise this technique. Our data also suggests that patients should be aware of the increased risk of developing knee donor site pain when three osteochondral plugs are harvested

Chondral defects in the knee have cartilage biomechanical differences due to defect size and orientation. This study examines how the tibiofemoral contact pressure is affected by increasing full-thickness chondral defect size on the medial and lateral condyle at full extension. Isolated full-thickness, square chondral defects increasing from 0.09cm. 2. to 1.0cm. 2. were created sequentially on the medial and lateral femoral condyles of six human cadaveric knees with intact ligaments and menisci. Chondral defects were created 1.0cm from the femoral notch posteriorly. The knees were fixed to a uniaxial load frame and loaded from 0N to 600N at full extension. Contact pressures between the femoral and tibial condyles were measured using pressure mapping sensors. The peak contact pressure was defined as the highest value in the 2.54mm. 2. area around the defect. The location of the peak contact pressure was determined relative to the centre of the defect. Peak contact pressure was significantly different between (4.30MPa) 0.09cm. 2. and (6.91MPa) 1.0cm. 2. defects (p=0.04) on the medial condyle. On the lateral condyle, post-hoc analysis showed differences in contact pressures between (3.63MPa) 0.09cm. 2. and (5.81MPa) 1.0cm. 2. defect sizes (p=0.02). The location of the stress point shifted from being posteromedial (67% of knees) to anterolateral (83%) after reaching a 0.49cm. 2. defect size (p < 0.01) in the medial condyle. Conversely, the location of the peak contact pressure point moved from being anterolateral (50%) to a posterolateral (67%) location in defect sizes greater than 0.49cm. 2. (p < 0.01). Changes in contact area redistribution and cartilage stress from 0.49cm. 2. to 1.0cm. 2. impact adjacent cartilage integrity. The location of the maximum stress point also varied with larger defects. This study suggests that size cutoffs exist earlier in the natural history of chondral defects, as small as 0.49cm. 2. , than previously studied, suggesting a lower threshold for intervention

The objectives of the study were to investigate demographic, injury and surgery/treatment-associated factors that could influence clinical outcome, following Autologous Chondrocyte Implantation (ACI) in a large, “real-world”, 20 year longitudinally collected clinical data set. Multilevel modelling was conducted using R and 363 ACI procedures were suitable for model inclusion. All longitudinal post-operative Lysholm scores collected after ACI treatment and before a second procedure (such as knee arthroplasty but excluding minor procedures such as arthroscopy) were included. Any patients requiring a bone graft at the time of ACI were excluded. Potential predictors of ACI outcome explored were age at the time of ACI, gender, smoker status, pre-operative Lysholm score, time from surgery, defect location, number of defects, patch type, previous operations, undergoing parallel procedure(s) at the time of ACI, cell count prior to implantation and cell passage number. The best fit model demonstrated that for every yearly increase in age at the time of surgery, Lysholm scores decreased by 0.2 at 1-year post-surgery. Additionally, for every point increase in pre-operative Lysholm score, post-operative Lysholm score at 1 year increased by 0.5. The number of cells implanted also impacted on Lysholm score at 1-year post-op with every point increase in log cell number resulting in a 5.3 lower score. In addition, those patients with a defect on the lateral femoral condyle (LFC), had on average Lysholm scores that were 6.3 points higher one year after surgery compared to medial femoral condyle (MFC) defects. Defect grade and location was shown to affect long term Lysholm scores, those with grade 3 and patella defects having on average higher scores compared to patients with grade 4 or trochlea defects. Some of the predictors identified agree with previous reports, particularly that increased age, poorer pre-operative function and worse defect grades predicted poorer outcomes. Other findings were more novel, such as that a lower cell number implanted and that LFC defects were predicted to have higher Lysholm scores at 1 year and that patella lesions are associated with improved long-term outcomes cf. trochlea lesions

Abstract. Introduction. This study aimed to assess the effect of PRP on knee articular cartilage content (thickness and/or volume) and establish if there is a correlation between changes in cartilage and clinical outcomes in patients with knee osteoarthritis. Methodology. A systematic review was performed following the Cochrane methodology. Studies were included if they reported on cartilage content with MRI or Ultrasound before and after the injection. A random-effects model meta-analysis was performed. Results. 11 studies (n=786) from 1,453 records met the inclusion criteria, with five (n=444) being RCTs. The PRP treatment protocol varied widely. Follow-up ranged from 6–12 months. Eight studies reported increase in cartilage content in the PRP group as compared to control (four showing significant difference). In meta-analysis: PRP treatment was not associated with a significant increase in cartilage thickness in medial and lateral femoral condyle, or in the overall cartilage content (4 studies, n=187, Hedges’ g: 0.079; 95%CI: 0.358-0.516; p=0.723). Meta-analysis of 3 RCTs (n=112) showed no significant difference in increasing cartilage content overall with PRP injections compared with no PRP (Hedges’ g: 0.217; 95%CI: -0.177 – 0.611; P=0.281). There was no correlation between changes in cartilage and clinical outcomes following PRP treatment. Conclusion. Treatment of knee osteoarthritis with PRP is not associated with a significant increase in articular cartilage content and any effect on cartilage is not associated with better clinical outcomes. A multi-centre, adequately powered RCT, with a standardized preparation / administration protocol assessing long-term effect of PRP in knee osteoarthritis is needed to guide clinical care

Abstract. Introduction. The incidence of significant acute chondral injuries with patella dislocation is around 10–15%. It is accepted that chondral procedures should only be performed in the presence of joint stability. Methodology. Patients were identified from surgeon/hospital logs. Patient demographics, lesion size and location, surgical procedure, patient reported outcome measures, post-operative MR imaging and complications were recorded. PROMs and patient satisfaction was obtained. Results. 20 knees (18 patients) were included. Mean age was 18.6 years (range; 11–39) and the mean follow-up was 16.6 months (range; 2–70). The defect locations were the lateral femoral condyle (9/20; 45%), patella (9/20; 45%), medial femoral condyle (1/20; 5%) and the trochlea (1/20; 5%). The mean defect size was 2.6cm2. Twelve knees were treated with cartilage fixation, 5 with microfracture and 3 with OATS. At follow up, the overall mean Lysholm score was 77.4 (± 17.1) with no chondral regenerative procedure being statistically superior. There was no difference in Lysholm scores between those patients having acute medial patellofemoral ligament reconstruction versus medial soft tissue plication (p=0.59). Five (25%) knees required re-operation (one arthroscopic arthrolysis; one patella chondroplasty; two removal of loose bodies; one implant adjustment). Overall 90% responded as being satisfied with surgery. Conclusion. Our aggressive pathway to identify and treat acute cartilage defects with early operative intervention and patella stabilisation has shown high rates of satisfaction and Lysholm scores with no major revisions. The full range of chondral restoration options should be considered by surgeons managing these patients

In living normal knee the lateral femoral condyle rolls posteriorly more than the medial side to the extent that in deep flexion the lateral femoral condyle sublux from the tibial surface (Nakagawa et al). The purpose of this presentation is to study the tibiofemoral movement in patients who had full flexion after total knee replacements and to compare it with that of normal knee. 23 knees were scanned using SIEMENS SIREMOBILE Iso-C with 3D Extension C-arm. The system is able reconstruct 3D images that can be viewed from deferent angle and precise measurements of distances between the deferent components of the implant can be made. The knee was scanned while the patient is sitting in kneeling position with the calf touching the thigh (flexion of over 150degree. All the cases studied showed a variable roll back between the medial and lateral femoral condyle. In all cases the lateral roll back was much more than the medial. In 14 cases we confirmed lateral condyle subluxation similar to what is seen in normal knee. The position of the foot (internal or external rotation) during scanning did not affect the lateral femoral condyle role back. Although previous studies have shown paradoxical types of tibiofemoral movement in patients who have total knee replacements throughout the range of movement, the knees in patients who had full flexion after TKA tend to have the same tibiofemoral movement as the normal knee in deep flexion. The lateral femoral condyles spin off or subluxation could adversely affect the implant components especially if the design does not accommodate this movement. The lateral femoral condyle may sublux from the tibia during kneeling inpatients who had full flexion after TKA. These findings should call for changes in the implant design to accommodate the lateral condyle roll back

Introduction: In living normal knee the lateral femoral condyle rolls posteriorly more than the medial side to the extent that in deep flexion the lateral femoral condyle sublux from the tibial surface(Nakagawa et al). The purpose of this presentation is to study the tibiofemoral movement in patients who had full flexion after total knee replacements and to compare it with that of normal knee. Materials and Methods: 23 knees were scanned using SIEMENS SIREMOBILE Iso-C with 3D Extension C-arm. The system is able reconstruct 3D images that can be viewed from deferent angle and precise measurements of distances between the deferent components of the implant can be made. The knee was scanned while the patient is sitting in kneeling position with the calf touching the thigh (flexion of over 150degree). Results: All the cases studied showed a variable roll back between the medial and lateral femoral condyle. In all cases the lateral roll back was much more than the medial. In 14 cases we confirmed lateral condyle subluxation similar to what is seen in normal knee. The position of the foot (internal or external rotation) during scanning did not affect the lateral femoral condyle role back. Discussion: Although previous studies have shown paradoxical types of tibiofemoral movement in patients who have total knee replacements throughout the range of movement, the knees in patients who had full flexion after TKA tend to have the same tibiofemoral movement as the normal knee in deep flexion. The lateral femoral condyles spin off or subluxation could adversely affect the implant components especially if the design does not accommodate this movement. Conclusion: The lateral femoral condyle may sublux from the tibia during kneeling in patients who have full flexion after TKA. These findings should call for changes in the implant design to accommodate the lateral condyle roll back

Objectives. Throughout the 20th Century, it has been postulated that the knee moves on the basis of a four-bar link mechanism composed of the cruciate ligaments, the femur and the tibia. As a consequence, the femur has been thought to roll back with flexion, and total knee arthroplasty (TKA) prostheses have been designed on this basis. Recent work, however, has proposed that at a position of between 0° and 120° the medial femoral condyle does not move anteroposteriorly whereas the lateral femoral condyle tends, but is not obliged, to roll back – a combination of movements which equates to tibial internal/ femoral external rotation with flexion. The aim of this paper was to assess if the articular geometry of the GMK Sphere TKA could recreate the natural knee movements in situ/in vivo. Methods. The pattern of knee movement was studied in 15 patients (six male: nine female; one male with bilateral TKAs) with 16 GMK Sphere implants, at a mean age of 66 years (53 to 76) with a mean BMI of 30 kg/m. 2. (20 to 35). The motions of all 16 knees were observed using pulsed fluoroscopy during a number of weight-bearing and non-weight-bearing static and dynamic activities. Results. During maximally flexed kneeling and lunging activities, the mean tibial internal rotation was 8° (standard deviation (. sd. ) 6). At a mean 112° flexion (. sd. 16) during lunging, the medial and lateral condyles were a mean of 2 mm (. sd. 3) and 8 mm (. sd. 4) posterior to a transverse line passing through the centre of the medial tibial concavity. With a mean flexion of 117° (. sd. 14) during kneeling, the medial and lateral condyles were a mean of 1 mm (. sd. 4) anterior and 6 mm (. sd. 4) posterior to the same line. During dynamic stair and pivoting activities, there was a mean anteroposterior translation of 0 mm to 2 mm of the medial femoral condyle. Backward lateral condylar translation occurred and was linearly related to tibial rotation. Conclusion. The GMK Sphere TKA in our study group shows movements similar in pattern, although reduced in magnitude, to those in recent reports relating to normal knees during several activities. Specifically, little or no translation of the medial femoral condyle was observed during flexion, but there was posterior roll-back of the lateral femoral condyle, equating to tibiofemoral rotation. We conclude that the GMK Sphere is anteroposteriorly stable medially and permits rotation about the medial compartment. Cite this article: Professor G. Scott. Can a total knee arthroplasty be both rotationally unconstrained and anteroposteriorly stabilised?: A pulsed fluoroscopic investigation. Bone Joint Res 2016;5:80–86. DOI: 10.1302/2046-3758.53.2000621

Introduction. Oriental people habitually adopt formal sitting and squatting postures, the extreme flexion of the knees allowing of this. The influence exercised by pressure and posture are, therefore, found at the posterior side of knee joint. However, we don't have many report about articular cartilage of posterior femoral condyle. Objectives. The purpose of this study was to reveal the accurate prevalence and related factors to the presence of degenerative changing of the articular cartilage of posterior femoral condyle in cadaveric knee joints. Methods. One hundred and thirty two knees from 66 cadavers (42 male knees and 24 female knees, formalin fixed, Japanese anatomical specimens) were included in this study. The average age of the cadavers was 81.4 (56–101) years. Knees were macroscopically evaluated the depth of cartilage degeneration of the patellofemoral joint, medial and lateral femoral condyle, medial and lateral posterior femoral condyle following the Outerbridge's classification. Grading was as follows: Grade 1: normal cartilage or softening and swelling of the cartilage. Grade 2: partial-thickness defect which did not reach the subchondral bone and was less than 1.3 cm in diameter. Grade 3: partial-thickness defect which did not reach the subchondral bone and was more than 1.3 cm in diameter. Grade 4: exposed subchondral bone and visible reactive tissue formation. When there were multiple lesions of different Outerbridge's classification grades, the sizes of the lesions were added up. Lesions with degenerative changes more severe than Outerbridge's classification grade 3 were regarded as OA lesions. Statistical analysis was performed to reveal the correlation between the occurrences of cartilage degeneration of medial and lateral posterior femoral condyle and medial and lateral femoral condyle and gender. Results. The prevalence of OA-positive was 48.5% (64 knees). Analyzing in the prevalence in gender, male was 31% (26 knees) OA-positive, female was 79.2% (38knees) OA-positive. The frequency of OA-positive was significantly higher in females than in males (P < 0.001). The prevalence of OA-positive in posterior condyle was 53.1% (34 knees) in 64 knees of OA-positive. Analyzing in the prevalence in gender, male was 15.4% (4 knees) in 26 knees of OA-positive, female was 78.4% (30knees) in 38 knees of OA-positive. The frequency of OA-positive in posterior condyle was significantly higher in females than in males (P < 0.001). Conclusions. In this study, the prevalence of OA-positive in posterior condyle was evaluated in cadaveric knees. The prevalence of OA-positive in posterior condyle was 53.1% in OA-positive knees, and was significantly correlated with the gender