Abstract. INTRODUCTION. This study aimed to examine how physical activity and health-related quality of life (HRQoL) evolved over the first year after total knee replacement (TKR) for patients with and without post-operative chronic knee pain. METHODS. 83 adults participating in the PEP-TALK, a RCT testing the effectiveness of a behaviour change physiotherapy intervention versus usual rehabilitation post-primary TKR, were analysed. UCLA Activity Score and EQ-5D-5L values for participants with and without chronic knee pain (14 points or lower in the Oxford Knee Score Pain Subscale at six months post-TKR) were compared at six and 12 months post-TKR. We evaluated recovery trajectory those with or without chronic pain at these time points. RESULTS. Participants with chronic knee pain, UCLA Activity Score remained unchanged between baseline to six months (mean: 3.8 to 3.8), decreasing at 12 months (mean: 3.0). Those without post-operative chronic knee pain reported a improvement in physical activity from baseline to six months (mean: 4.0 vs 4.9), plateauing at 12 months (mean: 4.9). Participants with chronic knee pain reported lower baseline HRQoL, although both groups improved mean health utility over one year. Of participants who were not defined as being in chronic pain at six months, 8.5% returned to a chronic pain categorisation by 12 months. CONCLUSION. People with chronic knee pain post-TKR report poorer physical activity and HRQoL scores post-operatively. Monitoring outcomes longer than six months may be indicated as those without chronic knee pain initially post-TKR remain at risk of reverting to chronic knee pain 12 months post-TKR

Aims. The primary aim of this study was to assess whether pain in the contralateral knee had a clinically significant influence on the outcome of total knee arthroplasty (TKA) according to the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) score. Secondary aims were to: describe the prevalence of contralateral knee pain; identify if it clinically improves after TKA; and assess whether contralateral knee pain independently influences patient satisfaction with their TKA. Methods. A retrospective cohort of 3,178 primary TKA patients were identified from an arthroplasty database. Patient characteristics, comorbidities, and WOMAC scores were collected preoperatively and one year postoperatively for the index knee. In addition, WOMAC pain scores were also collected for the contralateral knee. Overall patient satisfaction was assessed at one year. Preoperative contralateral knee pain was defined according to the WOMAC score: minimal (> 78 points), mild (59 to 78), moderate (44 to 58), and severe (< 44). Multivariate regression analysis was used to adjust for confounding. Results. According to severity there were 1,425 patients (44.8%) with minimal, 710 (22.3%) with mild, 518 (16.3%) with moderate, and 525 (16.5%) with severe pain in the contralateral knee. Patients in the severe group had a greater clinically significant improvement in their functional WOMAC score (9.8 points; p < 0.001). Only patients in the moderate (22.9 points) and severe (37.8 points) groups had a clinically significant improvement in their contralateral knee pain (p < 0.001), but they were significantly less likely to be satisfied with their TKA (moderate: odds ratio (OR) 0.64, 95% confidence interval (CI) 0.4 to 0.92, p = 0.022; severe: OR 0.57, 95% CI 0.39 to 0.82, p = 0.002). Conclusion. Contralateral knee pain did not impair improvement in the WOMAC score after TKA, and patients with the most severe contralateral knee pain had a clinically significantly greater improvement in their functional outcome. More than half the patients presenting for TKA had mild-to-severe contralateral knee pain, most of whom had a clinically meaningful improvement but were significantly less likely to be satisfied with their TKA. Cite this article: Bone Joint J. 2020;102-B(1):125–131

Aims. This study aimed to determine the expression and clinical significance of a cartilage protein, cartilage oligomeric matrix protein (COMP), in knee osteoarthritis (OA) patients. Methods. A total of 270 knee OA patients and 93 healthy controls were recruited. COMP messenger RNA (mRNA) and protein levels in serum, synovial fluid, synovial tissue, and fibroblast-like synoviocytes (FLSs) of knee OA patients were determined using enzyme-linked immunosorbent assay, real-time polymerase chain reaction, and immunohistochemistry. Results. COMP protein levels were significantly elevated in serum and synovial fluid of knee OA patients, especially those in the advanced stages of the disease. Serum COMP was significantly correlated with radiological severity as well as measures of body composition, physical performance, knee pain, and disability. Receiver operating characteristic curve analysis unveiled a diagnostic value of serum COMP as a biomarker of knee OA (41.64 ng/ml, area under the curve (AUC) = 1.00), with a sensitivity of 99.6% and a specificity of 100.0%. Further analysis uncovered that COMP mRNA expression was markedly upregulated in the inflamed synovium of knee OA, consistent with immunohistochemical staining revealing localization of COMP protein in the lining and sub-lining layers of knee OA inflamed synovium. Most notably, relative COMP mRNA expression in knee OA synovium was positively associated with its protein levels in serum and synovial fluid of knee OA patients. In human knee OA FLSs activated with tumour necrosis factor-alpha, COMP mRNA expression was considerably up-regulated in a time-dependent manner. Conclusion. All results indicate that COMP might serve as a supportive diagnostic marker for knee OA in conjunction with the standard diagnostic methods. Cite this article: Bone Joint Res 2024;13(6):261–271

Aims. This study investigated the effects of transcatheter arterial embolization (TAE) on pain, function, and quality of life in people with early-stage symptomatic knee osteoarthritis (OA) compared to a sham procedure. Methods. A total of 59 participants with symptomatic Kellgren-Lawrence grade 2 knee OA were randomly allocated to TAE or a sham procedure. The intervention group underwent TAE of one or more genicular arteries. The control group received a blinded sham procedure. The primary outcome was knee pain at 12 months according to the Knee injury and Osteoarthritis Outcome Score (KOOS) pain scale. Secondary outcomes included self-reported function and quality of life (KOOS, EuroQol five-dimension five-level questionnaire (EQ-5D-5L)), self-reported Global Change, six-minute walk test, 30-second chair stand test, and adverse events. Subgroup analyses compared participants who received complete embolization of all genicular arteries (as distinct from embolization of some arteries) (n = 17) with the control group (n = 29) for KOOS and Global Change scores at 12 months. Continuous variables were analyzed with quantile regression, adjusting for baseline scores. Dichotomized variables were analyzed with chi-squared tests. Results. Overall, 58 participants provided questionnaire data at 12 months. No significant differences were found for the primary and secondary outcomes, with both groups improving following the procedure. At 12 months, KOOS pain scores improved by 41.3% and 29.4% in the intervention and control groups, respectively. No adverse events occurred. Subgroup analysis indicated that the complete embolization group had significantly better KOOS Sports and Recreation, KOOS Quality of Life, and Global Change scores than the control group; 76.5% of participants who received complete embolization reporting being moderately or much better compared to 37.9% of the control group. Conclusion. TAE might produce benefits above placebo, but only when complete embolization of all genicular arteries is performed. Further comparative studies are required before definitive conclusions regarding the effectiveness of TAE can be made. Level of evidence: I. Cite this article: Bone Jt Open 2023;4(3):158–167

Aims. To examine the long-term outcome of arthrodesis of the hip undertaken in a paediatric population in treating painful arthritis of the hip. In our patient population, most of whom live rurally in hilly terrain and have limited healthcare access and resources, hip arthrodesis has been an important surgical option for the monoarticular painful hip in a child. Methods. A follow-up investigation was undertaken on a cohort of 28 children previously reported at a mean of 4.8 years. The present study looked at 26 patients who had an arthrodesis of the hip as a child at a mean follow-up of 20 years (15 to 29). Results. The mean Harris Hip Score (HHS) increased from 39.60 (SD 11.06) preoperatively to 81.02 (SD 8.86; p = 0.041) at final review. At latest follow-up, the HHS was found to be excellent in four patients (15%), good in 11 (42%), and fair in 11 (42%). A total of 16 patients (62%) reported mild low back pain, five (19%) had moderate pain, and five (19%) patients had no back pain. Mild ipsilateral knee pain was reported by 19 (73%), moderate pain by one (4%), and no pain by six (23%) patients. Mild contralateral hip pain was reported by ten patients (38%), and no pain by 16 (62%). The 36-Item Short Form Health Survey scores were very good in four patients (15%), good in 18 (70%), and poor in four (15%), with a mean score of 70.92 (SD 12.65). Of 13 female patients who had given birth, 12 did so with uncomplicated vaginal delivery. All patients had to modify their posture for toileting, putting on lower body clothes, foot care, and putting on shoes. Conclusion. Our results show that with hip arthrodesis, most patients have relatively good function at long-term follow-up, although some pain is experienced in adjacent joints, and modification in some activities of daily living is common. Cite this article: Bone Joint J 2022;104-B(9):1089–1094

Aims. It is not clear whether anterior knee pain and osteoarthritis (OA) of the patellofemoral joint (PFJ) are contraindications to medial unicompartmental knee arthroplasty (UKA). Our aim was to investigate the long-term outcome of a consecutive series of patients, some of whom had anterior knee pain and PFJ OA managed with UKA. Patients and Methods. We assessed the ten-year functional outcomes and 15-year implant survival of 805 knees (677 patients) following medial mobile-bearing UKA. The intra-operative status of the PFJ was documented and, with the exception of bone loss with grooving to the lateral side, neither the clinical or radiological state of the PFJ nor the presence of anterior knee pain were considered a contraindication. The impact of radiographic findings and anterior knee pain was studied in a subgroup of 100 knees (91 patients). Results. There was no relationship between functional outcomes, at a mean of ten years, or 15-year implant survival, and pre-operative anterior knee pain, or the presence or degree of cartilage loss documented intra-operatively at the medial patella or trochlea, or radiographic evidence of OA in the medial side of the PFJ. In 6% of cases there was full thickness cartilage loss on the lateral side of the patella. In these cases, the overall ten-year function and 15-year survival was similar to those without cartilage loss; however they had slightly more difficulty with descending stairs. Radiographic signs of OA seen in the lateral part of the PFJ were not associated with a definite compromise in functional outcome or implant survival. Conclusion. Severe damage to the lateral side of the PFJ with bone loss and grooving remains a contraindication to mobile-bearing UKA. Less severe damage to the lateral side of the PFJ and damage to the medial side, however severe, does not compromise the overall function or survival, so should not be considered to be a contraindication. However, if a patient does have full thickness cartilage loss on the lateral side of the PFJ they may have a slight compromise in their ability to descend stairs. Pre-operative anterior knee pain also does not compromise the functional outcome or survival and should not be considered to be a contraindication. Cite this article: Bone Joint J 2017;99-B:632–9

Aims. The primary aim was to assess whether robotic total knee arthroplasty (rTKA) had a greater early knee-specific outcome when compared to manual TKA (mTKA). Secondary aims were to assess whether rTKA was associated with improved expectation fulfilment, health-related quality of life (HRQoL), and patient satisfaction when compared to mTKA. Methods. A randomized controlled trial was undertaken, and patients were randomized to either mTKA or rTKA. The primary objective was functional improvement at six months. Overall, 100 patients were randomized, 50 to each group, of whom 46 rTKA and 41 mTKA patients were available for review at six months following surgery. There were no differences between the two groups. Results. There was no difference between rTKA and mTKA groups at six months according to the Western Ontario and McMaster Universities osteoarthritis index (WOMAC) functional score (mean difference (MD) 3.8 (95% confidence interval (CI) -5.6 to 13.1); p = 0.425). There was a greater improvement in the WOMAC pain score at two months (MD 9.5 (95% CI 0.6 to 18.3); p = 0.037) in the rTKA group, although by six months no significant difference was observed (MD 6.7 (95% CI -3.6 to 17.1); p = 0.198). The rTKA group were more likely to achieve a minimal important change in their WOMAC pain score when compared to the mTKA group at two months (n = 36 (78.3%) vs n = 24 (58.5%); p = 0.047) and at six months (n = 40 (87.0%) vs n = 29 (68.3%); p = 0.036). There was no difference in satisfaction between the rTKA group (97.8%; n = 45/46) and the mTKA group (87.8%; n = 36/41) at six months (p = 0.096). There were no differences in EuroQol five-dimension questionnaire (EQ-5D) utility gain (p ≥ 0.389) or fulfilment of patient expectation (p ≥ 0.054) between the groups. Conclusion. There were no statistically significant or clinically meaningful differences in the change in WOMAC function between mTKA and rTKA at six months. rTKA was associated with a higher likelihood of achieving a clinically important change in knee pain at two and six months, but no differences in knee-specific function, patient satisfaction, health-related quality of life, or expectation fulfilment were observed. Cite this article: Bone Joint J 2023;105-B(9):961–970

Aims. The aim of this study was to compare the incidence of anterior knee pain after antegrade tibial nailing using suprapatellar and infrapatellar surgical approaches. Patients and Methods. A total of 95 patients with a tibial fracture requiring an intramedullary nail were randomized to treatment using a supra- or infrapatellar approach. Anterior knee pain was assessed at four and six months, and one year postoperatively, using the Aberdeen Weightbearing Test – Knee (AWT-K) score and a visual analogue scale (VAS) score for pain. The AWT-K is an objective patient-reported outcome measure that uses weight transmitted through the knee when kneeling as a surrogate for anterior knee pain. Results. A total of 53 patients were randomized to a suprapatellar approach and 42 to an infrapatellar approach. AWT-K results showed a greater mean proportion of weight transmitted through the injured leg compared with the uninjured leg when kneeling in the suprapatellar group compared with the infrapatellar group at all timepoints at all follow-up visits. This reached significance at four months for all timepoints except 30 seconds. It also reached significance at six months at 0 seconds, and for one year at 60 seconds. Conclusion. The suprapatellar surgical approach for antegrade tibial nailing is associated with less anterior knee pain postoperatively compared with the infrapatellar approach. Cite this article: Bone Joint J 2019;101-B:1138–1143

Introduction. Up to 15 % of patients report anterior knee pain (AKP) after a total knee arthroplasty (TKA). The correlation of radiographic patellar measurements and post-operative AKP remains controversial. The purpose of this study was to determine whether any radiographic measurements can predict anterior knee pain after TKA. Methods. We performed a retrospective analysis of data on 343 patients who underwent a primary unilateral TKA between 2009–2012 at a single institution. Post-operative radiographs were evaluated with standing anteroposterior, lateral, and merchant views. Radiographic assessment was performed to assess posterior offset, Insall Salvati ratio, Blackburne, PP angle, Patella thickness, Congruence angle, Patella tilt, and patella displacement. Clinical function was assessed by the Kujala anterior knee pain scale at a minimum of 5 years. Patients were asked if they currently had anterior knee pain post-operatively by responding “yes” or “no.” There were 264 females and 79 males; the mean age at surgery was 64.2 ± 9.7 (range, 42–92 years) years; the mean BMI 31±5.8 kg/m. 2. (range, 18.8–49 kg/m. 2. ). Results. Of the 343 patients, 46 patients (13.4%) patients suffered persistent AKP at a minimum 5 years follow-up. Radiographic measurements were performed. Although we had large variations in congruence angle, patellar tilt and patellar displacement, these variations had no correlation with anterior knee pain (p=0.885). We were not able to detect statistical significance among clinical outcome Kujala score and patient reported AKP (p=0.713) at minimum 5 year follow-up. Discussion. Persistent anterior knee pain is troubling to patients and surgeons. Clinicians often get concerned when they see variability in these radiographic findings. Our findings suggest that variations in radiographic parameters do not predict anterior knee pain following total knee replacement surgery. For figures, tables, or references, please contact authors directly

Our purpose was to evaluate the incidence of anterior knee pain after ACL reconstruction and the associated affecting factors. The study assessed 50 ACL reconstructed knees: 29 males and 21 females. The age at surgery was from 14 to 39 years old, with 23.7 years old on the average. The ACL injury was unilateral in all cases, and the normal side was defined as the control. We treated chronic ACL-deficient knees by reconstruction of the ligament through a limited arthrotomy using one-third of the patellar tendon (BTB) with the Kennedy LAD as a graft. Anterior knee pain was classified into 4 group: absent, trace-mild, moderate, and severe. We evaluated the height of the patella, knee extension strength, anterior laxity, leg rotation, Lysholm score, and loss of extension. Anterior laxity and leg rotation were measured by a three-dimensional analyzer. Ten of the fifty knees (20%) had anterior knee pain. Knee extension strength (reconstructed side/control side) was 71.1% in the cases with anterior knee pain and 84.2% in the cases without anterior knee pain. A significant difference was found between these values. Regarding leg rotation, 4 knees showed normal leg rotation (physiological screw home movement) in the cases with anterior knee pain, compared to 31 knees in the cases without anterior knee pain. There was a significant difference in the incidence of anterior knee pain between the cases with normal leg rotation and the cases without. Other factors failed to show any significant correlation. In this study, knee extension strength and leg rotation had a correlation with anterior knee pain

Retrograde nailing of femoral shaft fractures has been a routine trauma practice option for approximately five years and may be technically advantaged in many situations. Earlier review of our antegrade experience revealed that 30% of standard nails are recognized to frequently cause pain (30%) and/or heterotopic ossification at the hip; knee pain of unclear etiology was found frequently as well (13%). This review of our preliminary experience with retrograde nails found a 30% frequency of nonspecific knee pain complaints at a mean of thirty-four months. No ectopic ossification was seen and no nails had been removed. The purpose of this study was to review the experience of patients who have undergone retrograde femoral nailing with regard to possible knee pain complaints. Chart and imaging records were reviewed retrospectively. Patients were contacted and interviewed by telephone to determine late pain complaints. From January 2000 through February 2002, eighteen patients were treated for twenty-two femoral shaft fractures. The group included ten males and and eight females of mean age 54.5 years (range, nineteen to ninety years). Treatment was with Synthes retrograde femoral nails, reamed and statically locked, inserted under fluoroscopic control on a radiolucent table using a Tenet™ leg holder. At thirty-four months, all fractures had healed primarily with no appreciable malalignment, no infections and no nonunions. No intraarticular free bodies or ectopic ossification were seen. Eleven patients were asymptomatic with regard to the index injured extremity. Five had mild to moderate pain, generally localized anteriorly, without associated articular symptoms and not requiring any analgesia. Two had severe symptoms of diffuse knee pain with radiographic degenerative changes noted, but these were cases with associated complex tibial plateau fractures to account for it. Even eliminating these two patients, fully five of sixteen patients (30%) without associated periarticular trauma at the knee had mild to moderate nondisabling anterior knee pain complaints after retrograde femoral nailing. The frequency of anterior knee pain complaints after retrograde femoral nailing is significant. Previous authors have found knee pain complaints in 27–29% of cases. We found no evidence of articular derangement in our patients undergoing retrograde femoral nailing in the absence of associated periarticular trauma at the knee, we confirm a 30% frequency of nonspecific knee pain complaints persisting at almost three years after injury. Patients should be made aware that, at intermediate-term follow-up, mild to moderate knee pain may be a result of this fracture treatment

Total knee arthroplasty (TKA) is one of the most common orthopaedic operations performed worldwide and it is largely successful in pain relief and functional recovery. However, when pain persists post-operatively the thorough evaluation must be instituted. Extra-articular causes of knee pain include; hip pathology, lumbar spine degenerative disease or radicular symptoms, focal neuropathy, vascular disease, and chronic regional pain syndrome. Intra-articular causes of knee pain: infection, crepitation/clunk, patella osteonecrosis, patella mal-tracking, soft tissue imbalance, malalignment, arthrofibrosis, component loosening, implant wear, ilio-tibial band irritation, and bursitis. Other causes of pain to rule out are component overhang with soft tissue irritation, recurrent hemarthrosis secondary to synovial impingement or entrapment, non-resurfaced patella, and metal sensitivity. A careful history may reveal previous knee surgeries with delayed healing or prolonged drainage, chronology of sign and symptoms, co-morbid medical conditions, jewel or metal sensitivity. Physical exam should help with specific signs in the operated knee. Targeted local anesthetic blocks are helpful and response to lumbar sympathetic blocks determines presence of CRPS. Lab tests are important: ESR, CRP, WBC, aspiration with manual cell count and diff, leucocyte esterase dipstick, RA titers, metal derm patch testing, nuclear scans, CT best for rotational malalignment, and MARS MRI. More recently patient satisfaction as an outcome measure has shown TKA results not satisfactory in 11- 18% of patients. A discordance of patient vs. surgeon satisfaction exists so the following factors may help improve this: correct patient selection, establishing and correlating surgeon-patient expectations, peri-operative optimization of patient co-morbidities to help avoid preventable complications, use of pre-operative and post-operative pathways. Satisfaction rates can best be improved by addressing the previous points with patients prior to TKA surgery

TKA is one of the most common orthopaedic operations performed worldwide and it is largely successful in pain relief and functional recovery. However, when pain persists post-operatively the thorough evaluation must be instituted. Extra-articular causes of knee pain include; hip pathology, lumbar spine degenerative disease or radicular symptoms, focal neuropathy, vascular disease, and chronic regional pain syndrome. Intra-articular causes of knee pain: infection, crepitation/ clunk, patella osteonecrosis, patella mal-tracking, soft tissue imbalance, malalignment, arthrofibrosis, component loosening, implant wear, ilio-tibial band irritation, and bursitis. Other causes of pain to rule out are component overhang with soft tissue irritation, recurrent hemarthrosis secondary to synovial impingement or entrapment, non-resurfaced patella, and metal sensitivity. A careful history may reveal previous knee surgeries with delayed healing or prolonged drainage, chronology of sign and symptoms, co-morbid medical conditions, jewel or metal sensitivity. Physical exam should help with specific signs in the operated knee. Targeted local anesthetic blocks are helpful and response to lumbar sympathetic blocks determines presence of CRPS. Lab tests are important: ESR, CRP, WBC, aspiration with manual cell count and diff, leukocyte esterase dipstick, RA titers, metal derm patch testing, nuclear scans, CT best for rotational malalignment,, and MARS MRI. More recently patient satisfaction as an outcome measure has shown TKA results not satisfactory in 11 – 18% of patients. A discordance of patient vs. surgeon satisfaction exists so the following factors may help improve this: correct patient selection, establishing and correlating surgeon-patient expectations, peri-operative optimisation of patient comorbidities to help avoid preventable complications, use of pre- and post-operative pathways. Satisfaction rates can best be improved by addressing the previous points with patients prior to TKA surgery

There is a recognised incidence of anterior knee pain following Anterior Cruciate Ligament (ACL) reconstruction using a patella tendon autograft. This study examined two group of patients both pre ACL ligament reconstruction and post ACL reconstruction using patella tendon grafts to define if anterior knee pain is a result of patella tendon harvest or a primary consequence of an ACL injury. The two groups of patients were best matched for age, sex and physical activity. The pre-operative group of twenty-five patients had a confirmed ACL rupture and exhibited symptoms of instability requiring an ACL reconstruction. The operative group of twenty-five patients were a minimum of a year post operation. The graft was harvested by an open procedure and the graft bone blocks were secured with interference screws. The patients’ anterior knee pain score was assessed using the Shelbourne scoring system that evaluates knee function in relation to anterior knee pain using five parameters. The maximum score is 100. The scores were compared using the unpaired student test. There was no significant age difference between the two groups, preoperative group age 32. 2 years (range 22 to 46) and postoperative age 34. 8years (range 19 to 48). The mean anterior knee pain score for the preoperative group was 71. 6 (49 to 100), the postoperative group was 77. 7 (45 to 100), this was not significantly different. We found no significant difference in knee function due to anterior knee pain between the two groups. Studies have shown significant anterior knee pain following hamstring reconstruction (Spicer). This study shows anterior knee pain in the ACL deficient knee is present prior to surgery. We conclude that patella tendon autografts produce no significant incidence of anterior knee pain post surgery

Introduction. A comprehensive met-analysis of anterior knee pain post intramedullary nailing of the tibia was performed by Katsoulis et al in 2006. The principle findings were that 47.4% of patients had anterior knee pain at 2 years post tibial nailing. Worse results were found following a patella tendon splitting approach when compared with a medial para-patellar tendon approach. These conclusions were drawn from 20 studies including 1460 patients. Currently both approaches to the proximal tibia for nailing are used at JCMH Blanchardstown. A retrospective study was performed to compare the results of tendon splitting and tendon sparing approaches to tibial nails and to compare the results of JCMH with those stated in literature. Method. Patients who underwent tibial nailing in 2007 and 2008 were identified using the hospital coding system. Those patients who were treated under the care of Mr Kenny had a medial para-tendinous approach and those treated the care of Mr O'Flanagan and Mr Keogh had a tendon splitting approach. Apart from the approach the nailing technique using the Trigen Knee Nail and the post operative physiotherapy protocol were identical. Follow up included questions regarding knee pain and return to previous function. Specifically: Knee pain that affects daily life, Knee pain on kneeling, Knee pain on ascending or descending stairs, Return to work and Return to sports or active hobbies. Results. 61 patients were treated with intra-medullary nailing between 2007 and 2008 43 were available for follow for the purposes of this study (70 %). 25 had nails inserted via a tendon splitting approach and 18 via a tendon sparing approach. Only 5% of patients had knee pain that affected daily life, 16 % had pain on kneeling, 90% of patients who were previously at work returned to work and 75% of patients who were previously engaged in sports were able to return to these activities. Discussion. These results are significantly better than the figures stated in literature in terms of knee pain, return to work and sports. There was no significant difference between the 2 approaches to the tibia again in contradiction of available literature

Excessive foot pronation has been considered to be related to anterior knee pain. We undertook a prospective study to test the hypothesis that exertional anterior knee pain is related to the static and dynamic parameters of foot pronation. Two weeks before beginning basic training lasting for 14 weeks, 473 infantry recruits were enrolled into the study and underwent two-dimensional measurement of their subtalar joint displacement angle during walking on a treadmill. Of the 405 soldiers who finished the training 61 (15%) developed exertional anterior knee pain. No consistent association was found between the incidence of anterior knee pain and any of the parameters of foot pronation. While a statistically significant association was found between anterior knee pain and pronation velocity (left foot, p = 0.05; right foot, p = 0.007), the relationship was contradictory for the right and left foot. Our study does not support the hypothesis that anterior knee pain is related to excessive foot pronation

Anterior knee pain is a frequent complaint of dissatisfied total knee arthroplasty patients. We hypothesize that the need to use the extensor mechanism to stabilise the knee during activity is a cause of anterior knee pain. Studies have shown that TKA patients often walk with a “quadriceps avoidance” gait, which may explain the phenomenon of anterior knee pain. Most TKA prostheses are designed to allow AP motion. This feature in knee implant design is to prevent the “kinematic conflict” that was predicted with the crossed four-bar-link model of knee motion, which holds that progressive posterior contact of the femur on the tibia (rollback) with flexion was obligatory for knee range of motion. It has been stated that preventing this motion overly “constrained” the knee and could lead to loosening and wear. Paradoxical motion has been seen with video fluoroscopy in knees after TKA. This motion is an anterior translation of the femur on the tibia early in knee flexion and is called paradoxical because it occurs opposite to the expected rollback. In fact, paradoxical motion is a consequence of the “unconstrained” articulation of the femoral component on the tibial component. During gait, just after heel strike as the foot is assuming a flat position on the floor, there is a significant vector of force from posterior to anterior. This vector has been calculated as 33% of body weight for walking at normal speed and could lead to a significant displacement of the femur forward on the tibia. It is countered by 1) the slope of the proximal tibia; 2) the articulation of the femur in the concavity of the tibial (with the firmly attached meniscus that deepens the concavity) on the medial side; and 3) the body mass vector combined with that of the contracting quadriceps. If a total knee prosthesis allows the femur to move forward, the posterior-to-anterior force just after heel strike acts to move the femur forward on the tibia (paradoxical motion). The patient, in an attempt to stabilise the knee, uses increased quadriceps contraction to prevent the forward motion of the femur. The forces required are significant and are not only found in the patella-femoral articulation but all through the retinaculum that covers the anterior part of the femur. As the extensor mechanism tires, patients begin using a quadriceps avoidance gait to adapt to the weakening extensor, and after a period of activity, the stress on the retinaculum leads to pain. AP stability can be improved through implant design by preventing AP motion through conformity of the femoral and tibial components. We have used a medially conforming ball-in-socket prosthesis as a revision component for patients with anterior knee pain, and have achieved resolution of the pain. Patients demonstrate a “posterior sag” at approximately 20 degrees of flexion (the degree of flexion that has the maximum posterior-to-anterior force during gait). When treated with a brace appropriate for stabilisation of the knee after PCL reconstruction, patients experienced a marked decrease in symptoms and this predicts a good result from revision surgery

From October 2005 to March 2014, we performed 46 arthroscopic surgeries for painful knee after knee arthroplasty. We excluded 16 cases for this study such as, unicompartmental knee arthroplasty, infection, patellar clunk syndrome, patellofemoral synovial hyperplasia, aseptic loosening, and follow-up period after arthroscopic surgery less than 6 months. Thirty cases matched the criteria. They had knee pain longer than 6 months after initial total knee arthroplasty (TKA), they had marked tenderness at medial and/or lateral tibiofemoral joint space, and also they complained walking pain with or without resting pain. Twenty one cases had initial TKA at our institute. In consideration of total number of TKA (n=489) in the period at our institute, incident rate of painful knee after initial TKA was 4.3%. Of 30 cases, 3 cases were male, and 27 cases were female. Types of implant were 4 in cruciate retaining type, 1 in cruciate substituting type, and 25 in posterior stabilized type. Age at the arthroscopy was 72 years old (51–87 years old), and period form initial TKA to pain perception was 18 months(1 – 144 months), and period from initial TKA to arthroscopic surgery was 29 months (6 – 125 months), and follow-up period after arthroscopy was 36 months (6 – 93 months). All arthroscopic debridement were performed through 3 portals, anteromedial, anterolateral, and proximal superomedial portal. Scar tissue impingements more than 5 mm wide were found in 87% of the cases both medial and lateral femorotibial joint spaces. Infrapatellar fat pad were covered with whitish scar tissue in all cases, and the scar tissue were connecting with the scar tissue which found at medial or lateral femorotibial joint spaces. We removed all scar tissue with motorized shaver or punches. At final follow-up, complete pain free in 63%, marked improvement in 3%, half improvement in 20%, slight improvement in 3%, and no change in 10% of the cases. Previously in the literatures, two reasons of the pain after total knee arthroplasty had been reported, patellar clunk syndrome, and patellar synovial hyperplasia. All cases reported this study had marked tenderness at tibiofemoral joint space. It was difficult to explain the tenderness by previously reported pathological mechanisms. We had to find another pathological mechanism to explain the pain of our cases. Painful knee due to scar tissue formation known as “infrapatellar contracture syndrome” after anterior cruciate ligament reconstruction surgery was previously reported. We hypothesized similar scar tissue formation should occur after TKA that caused painful knee. Continuity of the solid scar tissue between infrapatellar fat pad with the scar tissue at tibiofemoral joint space should be the cause of impingement at femorotibial joint even small size of scar tissue. From this study, we have to recognize that painful knee after TKA is not infrequent complication. And, if we could deny infection, and aseptic loosening in painful knee after TKA, arthroscopic debridement was good option to solve the pain. We could expect improvement of the pain more than half in 87% of cases

Introduction. Special high-flexion prosthetic designs show a small increase in postoperative flexion compared to standard designs and some papers show increased anterior knee pain with these prosthesis. However, no randomised controlled trails have been published which investigate difference in postoperative complaints of anterior knee pain. To assess difference in passive and active postoperative flexion and anterior knee pain we performed a randomized clinical trial including the two extremes of knee arthroplasty designs, being a high flex posterior stabilized rotating platform prosthesis versus a traditional cruciate retaining fixed bearing prosthesis. We hypothesised that the HF-PS design would allow more flexion, due to increased femoral rollback with less anterior knee pain than the CR design. We specifically assessed the following hypotheses:. Patients have increased flexion after HF-PS TKA compared to CR TKA, both passive and active. Patients show an increased femoral rollback in the HF-PS TKA as compared to the CR TKA. Patients receiving a HF-PS TKA design report reduced anterior knee pain relative to those receiving the CR TKA. Methods. In total 47 patients were randomly allocated to a standard cruciate retaining fixed bearing design (CR) in 23 patients and to a high-flexion posterior stabilized mobile bearing design (HF-PS) in 24 patients. Preoperative and one year postoperative we investigated active and passive maximal flexion. Furthermore, we used the VAS pain score at rest and during exercise and the Feller score to investigate anterior knee pain. A lateral roentgen photograph was used to measure femoral rollback during maximal flexion. Results. The HF-PS did show a significantly higher passive postoperative flexion; 120.8° (SD 10.3°) vs. 112.0° (SD 9.5°) for the CR group (p=0.004). The active postoperative flexion, VAS-pain score and Feller score did not show significant differences between both groups. Sub analysis with the HF-PS group showed a higher VAS-pain for the patients achieving ≥130° of flexion; 30.5 (SD 32.2) vs. 12.2 (SD 12.5) (p=0.16). The rollback was significantly lower in the CR group compared to the HF-PS group; 4.4 (SD 3.0) vs. 8.4 (SD 2.1). Conclusion. The present study showed a significant higher passive flexion in the Posterior Stabilised-High Flexion mobile bearing compared to a Cruciate Retaining fixed bearing prosthesis. However, this difference disappeared when comparing active flexion. The difference in passive flexion was probably related to a significantly lower rollback causing impingement in the CR prosthesis. No difference in anterior knee pain was found between both groups. However, a suggestion is raised that achieving high-flexion might lead to more patellofemoral complaints/anterior knee pain

Purpose: A relationship between vastus medialis oblique (VMO) strength and anterior pain and disability has been suggested. A biomechanical protocol was used to access the deficiency of the quadriceps muscles in patients with anterior knee pain. Methods and Results: A biomechanical evaluation was conducted on 54 patients with anterior knee pain (34 females and 20 males). All patient x-rays were normal through interpretation by a blinded radiologist. A Kistler force plate, a VICON motion analysis system and surface electromyography were used to quantify biomechanical function during isometric, walking and squatting exercises. For 42 of the 54 (78%) subjects, during isometric and walking exercises we observed that activation of the VMO, rectus femoris (RF) and vastus lateralis (VL) muscles of the symptomatic leg was not significantly different from those of the asymptomatic leg (p< 0.01). However, for 31 patients (57%) during the eccentric phase of the squat exercises, the symptomatic leg presented with high activation of VL compared to VMO and RF (p< 0.01). During the concentric phase, 45 patients (83%) presented with higher activation of the VL compared to the VMO. Conclusion: VMO activity during squatting for the symptomatic patient with anterior knee pain leg differs fundamentally during walking and isometric exercise compared to squatting tasks. Moreover, the relative contribution of the VL compared to the VMO during the eccentric phase of the squat exercises was different to those recorded during the concentric phase. Therefore, we suggest that maximal isometric and or isokinetic exercises are not sufficient to access the quadriceps function in relation to anterior knee pain. A thorough biomechanical assessment, including functional testing to reproduce the patient’s pain and locate the nature of the symptoms is suggested

Aim: To assess the prevalence of anterior knee pain after intramedullary nailing of the tibia and its socioeconomic impact. Methods: A retrospective, study of 251 consecutive tibial intramedullary nailings in 248 patients, aged less than 60 years at the time of injury. The minimum follow-up period was five years and the patients were assessed using a questionnaire and the Lysholm knee score. Results: The mean follow-up was 7.9 years. Anterior knee sensory disturbance was reported by 58% of patients. Anterior knee pain (AKP) was reported by 47%. This interfered with activities of daily living in 37%, work in 36% and sport in 57%. Pain on kneeling was mild in 54%, moderate in 34% and severe 12%. AKP improved with time in 73% patients and became worse in 4%. The Lysholm score rated 41% knees as excellent, 19% as good, 26% as fair and 14% as poor. Eighty-six percent of the patients returned to work. The presence of anterior knee pain prevented return to previous work in 10%. The type of work performed before and after injury respectively were; sedentary 26%/29%, walking-based 20%/27%, manual 38%/37%, heavy manual 16%/7%. Conclusions: Anterior knee pain persisted in 47% of patients after intramedullary nailing of the tibia. There was some decrease in symptoms with time and the majority of patients were able to return to work. However, anterior knee pain caused a significant disability in a small number and all patients should be warned of this problem before this type of surgery

The purpose of this study was to test the hypothesis that patella alta leads to a less favourable situation in terms of patellofemoral contact force, contact area and contact pressure than the normal patellar position, and thereby gives rise to anterior knee pain. A dynamic knee simulator system based on the Oxford rig and allowing six degrees of freedom was adapted in order to simulate and record the dynamic loads during a knee squat from 30° to 120° flexion under physiological conditions. Five different configurations were studied, with variable predetermined patellar heights. The patellofemoral contact force increased with increasing knee flexion until contact occurred between the quadriceps tendon and the femoral trochlea, inducing load sharing. Patella alta caused a delay of this contact until deeper flexion. As a consequence, the maximal patellofemoral contact force and contact pressure increased significantly with increasing patellar height (p < 0.01). Patella alta was associated with the highest maximal patellofemoral contact force and contact pressure. When averaged across all flexion angles, a normal patellar position was associated with the lowest contact pressures. Our results indicate that there is a biomechanical reason for anterior knee pain in patients with patella alta

Aims: Anterior knee pain is a common complaint of mixed aetiology, and in many cases no demonstrable cause is identified. For patients with persistant anterior knee pain, tibial tubercle transfer (TTT) can be a surgical option. The aim of this study is to assess the effectiveness of TTT for chronic anterior knee pain resistant to conservative treatment. Method: All patients with arthroscopically proven Chondromalacia patellae (CMP) without clinical evidence of patella instability, who have failed to respond to conservative treatment such as physiotherapy were included in the trial. They underwent TTT with a modified Fulkerson technique and then routine post-operative care with a cricket pad splint for 2–4 weeks. Pre and post-operative scores were obtained using a Kujala patello-femoral score, a visual analogue score for pain and a patient satisfaction score. The Outerbridge grading was used to score the severity of CMP at arthroscopy. Results: There were 50 TTT’s followed up (7 staged bilaterals) with a mean follow up of 32.4 months (5–88 months). There were significant improvement in the pre-operative and post-operative Kujala (p> 0.001) and visual analogue pain scores (p> 0.001). Of the 50 TTT’s 70% had an excellent or good result and 30% a fair or poor result. Moreover 76% claimed that they would have the same operation again for their condition. There was no significant correlation between Outerbridge grading and post-operative outcome. Complications include late anterior knee pain (10 cases), superficial wound infection (1 case), non-union of osteotomy (1 case) and tuberosity fracture (1 case). Conclusion: Anteromedial tibial tubercle transfer is a reliable and effective treatment for peristant anterior knee pain

There is a lack of information about the association between patellofemoral osteoarthritis (PFOA) and both adolescent Anterior Knee Pain (AKP) and previous patellar dislocations. This case-control study involved 222 participants from our knee arthroplasty database answering a questionnaire. 111 patients suffering PFOA were 1:1 matched with a unicompartmental tibiofemoral arthritis control group. Multivariate correlation and binary logistic regression analysis was performed, with odds ratios (ORs) and 95% confidence intervals (CIs) calculated. This analysis helps us assess the effect of both variables whilst adjusting for major confounders, such as previous surgery and patient-reported instability. An individual is 7.5 times more likely to develop PFOA if they have suffered adolescent AKP (OR 7.5, 95% CIs 1.51–36.94). Additionally, experiencing a patellar dislocation increases the likelihood of development of PFOA, with an adjusted odds ratio of 3.2 (95% CIs 1.25–8.18). A 44-year difference in median age of first dislocation was also observed between the groups. This should bring into question the traditional belief that adolescent anterior knee pain is a benign pathology. Patellar dislocation is also a significant risk factor. These patients merit investigation, we encourage clinical acknowledgement of the potential consequences when encountering patients suffering from anterior knee pain or patellar dislocation

Whereas thermography has already been used as an assessment of disease activity in some kinds of inflammatory arthritis, it is a new method for objektive pain evaluation in patients with joint prosthesis. To our knowledge, no study has tested the correlation between increase of temperature and anterior knee pain with total knee prosthesis yet. Thirteen patients were included in this study who suffered from anterior knee pain of the retinaculum patellae with total knee prosthesis. The patients were asked to walk 3 km before entering a room which was cooled down to 20 degrees Celsius. A black 1 cm times 4.5 cm square stripe was attached on the diameter of the patella and the patients rested for 20 minutes to cool down before thermographic fotos were taken from 90 degrees, 45 degrees, frontal medial and lateral. The evaluation of temperature difference of each side was performed by marking a 1cm times 2cm square field rectangular around the black stripe and comparing it with a reference point of the same size 3 cm distal of the field. The patients were compared with thirteen others, not suffering from anterior knee pain. Statistical analysis was performed using a t- test and a p value < 0.05 was considered to be significant. The temperature differences between the rectangular field and the reference point increased significantly on the medial (p= 0.00037) or lateral (p= 0.000002) pain side of the knee. The thirteen knees with knee pain had significantly higher temperature differences between medial and lateral temperature differences, than the knees without knee pain. We demonstrate a significant correlation between anterior knee pain and an increase of superficial skin temperature around the retinaculum patellae. To our knowledge, this is the first report of an objective assessment of pain of the retinaculum patellae with total knee prosthesis

Mechanical abnormalities of the patellofemoral joint are among the many causes that have been suggested for adolescent knee pain. This study seeks to identify these factors. Measurements of joint mobility and lower limb morphology were made on 446 pupils at a comprehensive school, 136 of whom had suffered knee pain in the previous year. The pupils with symptoms enjoyed sporting activities significantly more than their symptom-free contemporaries. Joint mobility, the Q-angle, genu valgum and anteversion of the femoral neck were not significantly different between those pupils with and those without anterior knee pain. Data on lower limb morphology of normal adolescents are presented. Examination of 52 hospital outpatients aged 13 to 36 years with anterior knee pain produced results comparable with those for the pupils. It is concluded that chronic overloading, rather than faulty mechanics, is the dominant factor in the genesis of anterior knee pain in adolescent patients

Aim. To determine if the location and pattern of knee pain as described by the patients using the knee pain map was comparable with the intra articular pathology found on arthroscopy as well as to facilitate diagnosis based on pain. Methods. There were fifty five consecutive patients with acute and chronic knee pain participating in the study and they subsequently underwent arthroscopy of the knee joint as therapeutic or diagnostic procedure in day surgery. Those patients with extra articular pathologies, referred pain hip, back and foot were excluded from the study. All the participants were consented for the study; subjective data was recorded on the standardised knee pain map that included visual analogue pain scale preoperatively on the day of admission for arthroscopy. The findings of the arthroscopy including EUA were recorded on the on standard arthroscopy forms used in our department by the operating surgeon. Results. Patients on the knee pain map most often recorded sharp/stabbing pain (72%), followed by diffuse dull pain (14.5%), mixed dull and sharp pain (10 %) and burning pain (3.5%). 82% of the localising pain pattern recorded on the knee pain map by the patients corresponded to the intra articular lesion found during knee arthroscopy. 18 % of the pain mapping location and pattern was not very specific to the intrarticular arthroscopic lesions. Conclusions. The results from our study indicate, majority of the patients could map the knee pain location and pattern correlating to the knee arthroscopic findings. Furthermore, the knee pain mapping can be used as a reliable tool to assist the clinician to determine the specific knee pain patterns correlating with intra-articular lesion

Objective of the study. To determine if the location and pattern of knee pain as described by the patients using the knee pain map was comparable with the intra articular pathology found on arthroscopy as well as to facilitate diagnosis based on pain. Methods. There were Sixty consecutive patients with acute and chronic knee pain participating in the study and they subsequently underwent arthroscopy of the knee joint as therapeutic or diagnostic procedure in day surgery. Those patients with extra articular pathologies, referred pain hip, back and foot were excluded from the study. All the participants were consented for the study; subjective data was recorded on the standardised knee pain map that included visual analogue pain scale preoperatively on the day of admission for arthroscopy. The findings of the arthroscopy including EUA were recorded on the on standard arthroscopy forms used in our department by the operating surgeon. Results. Patients on the knee pain map most often recorded sharp/stabbing pain (72%), followed by diffuse dull pain (14.5%), mixed dull and sharp pain (10 %) and burning pain (3.5%). 78 % of the localising pain pattern recorded on the knee pain map by the patients corresponded to the intra articular lesion found during knee arthroscopy. 18 % of the pain mapping location and pattern were not very specific to the intrarticular arthroscopic lesions and the rest were non specific. Conclusions. The majority of the patients could map the knee pain location and pattern correlating to the knee arthroscopic findings. The results from our study indicate that knee pain mapping can be used as a reliable tool to assist the clinician to determine the specific knee pain patterns correlating with discrete pathologic findings knee intra articular lesion

Objectives. To assess the effectiveness of a modified tibial tubercle osteotomy as a treatment for arthroscopically diagnosed chondromalacia patellae. Methods. A total of 47 consecutive patients (51 knees) with arthroscopically proven chondromalacia, who had failed conservative management, underwent a modified Fulkerson tibial tubercle osteotomy. The mean age was 34.4 years (19.6 to 52.2). Pre-operatively, none of the patients exhibited signs of patellar maltracking or instability in association with their anterior knee pain. The minimum follow-up for the study was five years (mean 72.6 months (62 to 118)), with only one patient lost to follow-up. Results. A total of 50 knees were reviewed. At final follow-up, the Kujala knee score improved from 39.2 (12 to 63) pre-operatively to 57.7 (16 to 89) post-operatively (p < 0.001). The visual analogue pain score improved from 7.8 (4 to 10) pre-operatively to 5.0 (0 to 10) post-operatively. Overall patient satisfaction with good or excellent results was 72%. Patients with the lowest pre-operative Kujala score benefitted the most. Older patients benefited less than younger ones. The outcome was independent of the grade of chondromalacia. Six patients required screw removal. There were no major complications. Conclusions. We conclude that this modification of the Fulkerson procedure is a safe and useful operation to treat anterior knee pain in well aligned patellofemoral joints due to chondromalacia patellae in adults, when conservative measures have failed

Achieving deep flexion of knee after total knee arthroplasty (TKA) is particularly desirable in some Asian and Middle Eastern who have daily or religious customs typically use full knee flexion. After TKA, some patients complained about anterior knee pain during deep knee flexion. We evaluated the efficacy of arthroscopic fat pad resection in a series of patients suffering from anterior knee pain associated with high flexion achievement after TKA. The efficacy of fat pad resection via arthroscopy for treating anterior knee pain associated with high flexion angle (average = 133.1°) was evaluated in eight knees of eight patients among 207 knees performed between 1996 and 1999. The mean age of patients was 71.1 years when the primary TKA was performed. All implatants were posterior stabilized type (IB-II, Nexgen PS and LPS). The symptom of anterior knee pain during deep knee flexion developed within one year after TKA in all cases. In addition to pain in eight knees, two patients have crepitation as the knee was flexed and extended and three patients had hydrarthrosis. Impingement and fibrosis of fat pad were confirmed, and fibrous structures were removed by arthroscopy. Before arthroscopy, the symptom obviously subsided after injection of local anesthesia into infrapatellar fat pad. Patellar clunk syndrome is also soft tissue impingement and suprapatellar fibrous nodule becomes entrapped intercondylar notch on the femoral component during knee flexion. On this point, these cases does not cause by patellar clunk syndrome. After fat pad resection, the symptom disappeared, and keeps symptom-free after a mean follow-up of six years five months in all cases. Any complications following fat pad resection, such as patella baja and necrosis, were not experienced. Those cases achieving higher flexion angle tended to experience severe pain and shorter time interval between TKA and arthroscopic surgery, suggesting impingement of the infrapatellar fat pad is closely related to deep flexion after TKA. These results demonstrate that the anterior knee pain due to repetitive infrapatellar fat pad impingement is one of the complications during deep knee flexion after TKA, and the arthroscopic fat pad resection is useful to relief the anterior knee pain. Because of our experience with patients encountering anterior knee pain, we have begun to remove 70 to 80% of the fat pad during the primary TKA procedure since 1999, and until today, none developed anterior knee pain thought to be associated with fat pad impingement, patellar baja nor patellar necrosis. We suggest that fat pad resection is necessary to prevent the anterior knee pain due to fat pad impingement during deep flexion in TKA

The prevalence of anterior knee pain in the general population is relatively high. Patellar height, and more specific patella alta, is one of the several factors that have been associated with anterior knee pain, but the precise mechanism by which patella alta leads to a less favourable situation in terms of patellofemoral contact force, contact area and contact pressure, is poorly understood. The recent availability of validated dynamic knee simulators and advances in the analysis of contact force and area, give us today the possibility to study the influence of patellar position and patellar height on patellofemoral biomechanical characterisitics. Simulating a knee squat in different configurations with variable predetermined patellar height, reveals a clear association of patella alta with the highest maximal patellofemoral contact force and contact pressure, probably as a consequence of the delay in tendofemoral contact. When averaged across all flexion angles, the normal height of the patella seems to be the most optimal position in terms of contact pressures. This may provide a biomechanical explanation for anterior knee pain in young patients with patella alta and in older patients following total knee prosthesis resulting in an altered patellar position in terms of height

Total knee arthroplasty (TKA) disturbs patellar blood flow, an unintended accompaniment to TKA that may be a cause for postoperative anterior knee pain. We compared patellar blood flow before and after medial parapatellar arthrotomy to pre- and postoperative anterior knee pain scores to ascertain whether disrupted patellar blood flow correlates with anterior knee pain following TKA. Blood flow measurements were performed at full extension and at 30°, 60°, 90° and 110° of flexion prior to and after medial arthrotomy in 50 patients (21 male, 29 female; mean age 73.1±8.6 years) undergoing TKA. Anterior knee pain was assessed using the pain intensity numeric rating scale. A significant decrease in blood flow was detected at 60°, 90°, and 110° of flexion (p values: 0.00314,< 0.0001,< 0.0001 respectively). The medial arthrotomy did not have a statistically significant influence on patellar blood flow in the Students’ t-test (margin of significance p& #61603;0.05) Nineteen patients exhibited an average 14% (range 1%–54%) increase in patellar blood perfusion at knee flexions of 90° and 110° after medial arthrotomy (p value: 0.32) Prior to TKA, 16 of the 50 patients (32%) complained of anterior knee pain (average NRS 7.12, range 5–10). At 6-month follow up, 4 of the 16 patients (25%) complained of moderate anterior pain (average NRS 5.7, range 5–6), while 8 of 16 (50%) patients reported discomfort (average NRS 3.5, range 2–4) around the patella. No statistically significant correlation was found between intraoperative findings on patellar blood flow and the presence of anterior knee pain

Introduction: Short term pain or discomfort after a knee replacement (TKR) is not uncommon, and is usually attributed to the surgical procedure. In this case report, we describe an unusual cause of knee pain following total knee replacement, and remind the reader of the need for a thorough assessment. Case Report: A 76 year-old male presented with pain in the knee and shin seven months following a TKR on the same side. The pain was dull, aching and constant in nature. There was no other significant past medical history. Pre-operative and immediate postoperative radiographs did not reveal any other abnormality. Clinical examination revealed no evidence of infection, and the motion in the knee ranged from 0–100 degrees. Radiographs revealed a lytic lesion in the proximal tibia just distal to the tibial prosthesis. Further investigations confirmed a diagnosis of renal carcinoma with bone metastases, with one of the lesions appearing in the proximal tibia. The lesion was treated with intralesional curettage, cementing and plate osteosynthesis. The knee pain improved and the mobility was restored. Follow-up radiographs at 6 months showed no evidence of local recurrence. Discussion: Knee pain following TKR may be attributed to the surgery or the knee implant. However, it is important to keep an open mind about the diagnosis. Local hyperaemia in the metaphysis of proximal tibia following TKR may have resulted in the seeding of metastasis. We elected for primary stabilization of the metastasis with cement and plate, rather than revision of the tibial component with a long intramedullary stem. As a result, rehabilitation was rapid and the risks of revision of the knee prosthesis were avoided

The aim of this study was to assess the outcome of patients who underwent ElmslieTrillat antero-medial tibial tubercle transfer for treatment of persistent symptomatic anterior knee pain due to chondromalacia patellae. We performed a prospective analysis of 23 patients who underwent Elmslie-Trillat antero-medial tibial tubercle transfers over a five year period for chronic anterior knee pain and an arthroscopic diagnosis of chondromalacia patellae. All patients who presented with anterior knee pain underwent an initial period of physiotherapy and all patients whose symptoms persisted following physiotherapy underwent arthroscopic assessment. Patients who continued to experience debilitating symptoms despite this initial treatment and who also had a diagnosis of chondromalacia patellae from arthroscopic assessment were listed for an Elmslie-Trillat tibial tubercle anteromedialisation. Patients who gave a history of instability or dislocation were excluded. The average age of patients undergoing surgery was 34 years (21–48 years) and the average time between arthroscopic diagnosis and surgery was 14 months. All patients who underwent surgery had pre and post operative KuJala patellofemoral scoring. The average pre-operative score was 54 (30–78) and post operative score 76 (46–100). The average post operative assessment was 25 months (6–62 months). Twenty one patients had improved post operative scores with one having a worse score and one score remaining unchanged following surgery. Nineteen patients felt that their symptoms had improved, three felt that there had been no change and one felt that they were worse after surgery. When asked if the improvement in symptoms had been worthwhile nineteen stated that they would undergo surgery again if in the same situation and four stated that they would not. The treatment of symptomatic chondromalacia patellae remains a challenge. Although a more selective approach to individuals with anterior knee pain is widely advocated in the literature this study demonstrates that good results can still be achieved in patients treated empirically with a tibial tubercle anteromedialisation

There are two types of pain, mechanical and non-mechanical. Mechanical pain hurts with movement/use, is not constant and is helped by morphine-type products. Non-mechanical pain is different. It is present 24 hours a day, often worse at night, and except for the pain of infection, is not relieved by morphine-type products. If the cause of mechanical pain can be determined, it can be corrected by an operation. The usual cause of postoperative mechanical knee pain nowadays is multifactorial, i.e. a combination of minor errors, none of which on their own would require revision. Non-mechanical pain, other than infection, is much more difficult to handle. The commonest cause is not really a pain complaint, it is disappointment due to a failure of expectation. It does not matter how often you tell patients, some patients still think they should step in a drive away. A lot of these failures of expectations become much more realistic by the end of year one. There are several other categories. Incipient osteoarthritis or sensitive people (The Princess and the Pea). If the pain complaints were severe with minimal arthritis, an operation is not likely to help. The patient on disability for no clear reason is unlikely to get a good result and Workmen's Compensation Board and motor vehicle accident patients are also a very bad prognostic sign and will often produce the postoperative painful knee. Preoperative use of large doses of morphine is also a very bad sign. It is not clear if it is the morphine, which influences the patient or the patient, who influences the morphine. There are several pain syndromes, some of which are purely psychiatric such as Conversion Disorders and Somatoform Pain Disorders. Treatment of purely psychiatric conditions should be a referral to a psychiatrist is in order. Complex regional pain syndrome is an organic pain disorder. Type 2 is causalgia or an actual nerve injury. This is unusual following knee replacement other than the odd drop foot, which even after recovery, leaves an area of dysaethesia on the dorsum of the foot. Type 1 used to be called reflex sympathetic dystrophy. This is not uncommon after total knee replacement. I managed to collect more than 40 cases. One problem is that the diagnosis to some extent is a diagnosis of exclusion. If the diagnosis can be made, then treatment is available including Cymbalta, Lyrica or Gabapentin. I have found most success with lumbar sympathetic blocks, but it is difficult to find someone, who can do these. Some patients have been treated with implantable electrical spinal stimulators with variable results. The current flavour of the month pain syndrome is called central sensitization. The theory is that if someone has pain for more than six months, then there will be changes in the brain, which will remain after the original pain goes away, hence, the title the pain in the brain syndrome. If this theory were correct, then we as arthroplasty surgeons have been collectively wasting our time for the last 40 years as no patient would have recovered. The likelihood, therefore, of this theory having any basis in reality is pretty remote. Fortunately, by the end of year one, the vast majority of our knee replacement patients are reasonably content with the procedure

Introduction. Anterior knee pain is a common presentation of patello-femoral dysfunction and patients with this disorder represent a significant proportion attending a specialist knee clinic. There is an on-going debate as to the cause and best treatment for such patients. Previous studies on patella-femoral morphology have suggested patella maltracking plays an important part in the aetiology but there had been no studies correlating maltracking with articular cartilage change. Methods. We studied 147 consecutive patients (294 knees) aged between 10 and 63 presenting with anterior knee pain. All underwent MRI tracking scan of their knees as part of the routine investigations. We analysed the prevalence of maltracking with respect to gender, laterality and age groups, as well as patello-femoral articular cartilage changes. Results. 52% of patients were found to have maltracking, of which 75% were bilateral. Furthermore, 66% of patients with maltracking had radiological evidence of patellar articular cartilage changes, corresponding to 61% of 294 knees examined. While majority of these occur at lateral facet, a proportion of medial facet changes (16%) is also seen. More significantly, while 25% of knees from patients with maltracking under the age of 20 are found to have changes on the patella cartilage, this increases to 93% by the age of 50 or above, with step-wise increment per decade of age (p<0.01). Conclusion. Our results demonstrate a strong correlation between anterior knee pain symptoms, patella maltracking and changes in patello-femoral joint cartilages of varying severity. This has implications on the management of these patients and would suggest early correction of maltracking is indicated to prevent deterioration in the patello-femoral joint

Recovery after femur fractures is slow, despite rapid bone union. Causes of disability require investigation. Forty patients with isolated, diaphyseal femur fractures treated with antegrade locked intramedullary nailing were prospectively studied. Functional outcome was measured using the Western Ontario – McMaster University Osteoarthritis Index (WOMAC) and Short Musculoskeletal Functional Assessment (SMFA). Pain scores from the groin, buttock, thigh, and knee six months following the injury were correlated with functional outcome. Severity of pain was highest at the knee. Both knee and thigh pain had strong correlations with functional outcome measures following diaphyseal femur fractures. Further investigation into post-traumatic pain is warranted. This study was performed to compare pain at the knee, thigh, buttock and groin with functional outcome scores 6 months following femur fractures. Pain at the knee and thigh correlated with functional outcome measures. Many patients with femoral fractures have prolonged disability. Knee pain is common, severe, and correlates with functional outcome. Forty skeletally-mature patients with diaphyseal femoral fractures treated with locked antegrade intramedullary nails were prospectively enrolled. Exclusion criteria included polytrauma, ipsilateral injuries, metaphyseal extension, and pathologic fractures. Functional outcomes were assessed using the Western Ontario-McMaster University Osteoarthritis Index (WOMAC) and the Short Musculoskeletal Function Assessment (SMFA). Patients were instructed to record pain in the groin, buttock, thigh or knee of the fractured extremity on a 10-point visual analog scale. Patients reported more pain at the knee (3.7 ± 3.1), compared to the thigh (2.5 ± 2.7), buttock (1.7 ± 2.7), and groin (1.0 ± 1.7) (p=0.003). Pain and functional outcomes were plotted on scatter graphs and correlations performed using the Spearman rank test. Strongest correlations were noted between knee pain and WOMAC pain (ρ=0.748, p< 0.001), function (ρ=0.701, p< 0.001), and SMFA (ρ=0.733, p< 0.001); and between thigh pain and WOMAC pain (ρ=0.705, p< 0.001), stiffness (ρ=0.707, p< 0.001), function (ρ=0.731, p< 0.001), and SMFA (ρ=0.723, p< 0.001). Weaker correlations were noted between groin and buttock pain and functional outcomes. Knee pain is common and severe after femur fractures. Knee and thigh pain correlate with functional outcomes. Further investigation should be directed to this common problem. Funding: Funding from Synthes Canada, Smith and Nephew Richards Canada, and the Lawson Health Research Institute was received in support of this study

We performed an advancement and medial transfer of the tibial tuberosity based on Fulkerson's principle to treat intractable anterior knee pain associated with patellofemoral maltracking diagnosed by dynamic MRI. Between January 1998 and July 2000 twenty-two patients had 28 knees operated for anterior knee pain. There were 4 men and 18 women with a mean age of 28 years (range 18-41). Indications for surgery were [a] failure to improve after six months of physiotherapy and [b] patellofemoral maltracking evident in dynamic MRI. Mean follow-up was for 37 months (23 – 42). Knee instability score modified by Fulkerson was employed for objective and subjective assessment. Objectively 22 (79%) knees achieved good to excellent results. Four knees (14%) had fair, and two (7%) had poor results. Excellent and very good results were seen in 20 knees. These patients were a younger age group (mean age 21 years) and had minimal degeneration (grade I-II) of the patellofemoral joints. Two patients achieved good results. One of them had moderate (grade III) and one minimal (II) arthritis. Three knees with fair results had advanced (grade IV or V) and one had moderate (grade III) arthritis. Out of two patients who had a poor result, one had advanced degeneration (grade V) that later required a patellofemoral joint resurfacing. The other was a 24 year old woman with grade II changes. She was treated by the pain therapy team. Anterior displacement of the tuberosity in the presented study was kept to 5 mm to avoid the possible complications of wound break down. The overall length and depth of the osteotomy was also reduced to minimise risk of fracture and commence early mobilisation. Based on our results there is a strong case of justification for Anteromedialisation of tibial tuberosity using a smaller length of osteotomy and lesser degree of anteriorisation in carefully selected patients with Patellofemoral arthralgia associated with maltracking patella

Anterior knee pain in adolescents is generally recognised as a common but benign self-limiting condition. Although many operative procedures for its treatment have been proposed, there is little statistical evidence that they are more effective than expectant management. A group of 54 adolescent girls has been followed for two to eight years from presentation with anterior knee pain. Although some pain persisted in the majority, in many the symptoms declined in severity. This study provides a baseline for comparison with the results of operative intervention; it is suggested that surgical treatment is unproven and unnecessary

Introduction. Acute poliomyelitis is a very rare disease in western countries, however the remnant of the pathology can be find among the adult patients. In poliomyelitis, sensation is normal and patients may suffer from painful etiologies. Total knee arthroplasty (TKA) with non-hinged or semi hinged prosthesis systems may be a good options to relief the pain in poliomyelitic patients, however the knee remains unstable. Using the hinged system implant may be the good option to resolve the late. Although the main concern in case of hinged implant usage is the mechanical stress which is directly transferred to the bone surface in contact with the implant. This may leads to implant mobilization and consequently failure. Methods and Materials. From 2004 to 2014, 14 TKA were performed in poliomyelitic patients with secondary knee pain. All patients were presented with extensor compartment hyposthenia and reduced antigravity function. In all patients a third generation rotating hinged knees (RHK) implant system (Zimmer, Warsaw, IN, USA) was applied. Bilateral TKA was performed in only one case. The mean age at the time of surgery was 56 years (ranged 48–77). Mean follow-up was 60 months (24–112). Results Due to post-operative infection, one patient underwent knee arthrodesis and excluded from the study. In one case, patellar fracture occurred 3 month following the surgery and treated non-surgically. Pain relief was observed in all patients following the surgery without any major complication. Mean objective score according to knee society knee scoring system was improved from 28 (16–51) preoperatively to 79 (72–88) postoperatively. Mean functional score was improved from 24 (5–35) preoperatively to 66 (50–70) postoperatively. At last follow up the mean range of motion was 90° (75°−100°). Following radiographic control at last follow-up all implants was stable without any sign of failure such as mobilization, radiolucency line or osteolysis. Conclusion. Providing stable knee implant system is the most important factor in addition to pain relief in case of poliomyelitic patients with knee pain. In our experience, third generation RHK supplied satisfactory clinical results in poliomyelitic patients supplying good implant stability without interfere with existing intrinsic stability of the lower limb. We believe that good results were achieved due to particular specification of RHK implant including mild 3° of hyperextension and weight distribution mode in which 95% transfer to polyethylene insert and only 5% to hinged compartment that help to restore the stability in such a particular patients also in case of late post-polio syndrome

We assessed patellofemoral joint function by combining the measurement of maximal isometric extensor torque at the knee with clinical and radiological measurements in order to calculate the patellofemoral contact force. Eighteen volunteers established the normal ranges of results and the reliability of the system. Of the 39 patients with a variety of knee problems, 29 had anterior knee pain, and all had a subsequent arthroscopy. Patients with anterior knee pain and lesions in the patellar cartilage had significantly reduced isometric contact forces, but those with normal patellofemoral cartilage had normal contact forces. Our method may be useful in providing an objective assessment of anterior knee pain and a quantitative means of monitoring its treatment

Introduction: Poor proprioception and imbalance between quadriceps and hamstrings have been suggested as causes for anterior knee pain. The aim of our study was to compare the proprioception of patients with anterior knee pain to a normal population and to compare the activity of quadriceps and hamstrings using electromyography (EMG) in the 2 groups. Methods: Patients and controls between the ages 11–25 yrs were recruited into the study. The proprioception (stability index) of the patients and controls was tested using the Biodex stability system. This computerised system tests the ability of a person to balance his/her own body on a platform that moves in various directions. Surface EMG was recorded from the quadriceps and hamstrings during this test. EMG was also recorded as the patients and controls stepped onto a 20cm step. EMG activity was normalised to levels elicited during maximal isometric contractions. Results: 18 patients and 27 controls were recruited. We found no significant difference between the groups in the EMG intensity of vastus lateralis relative to biceps femoris, or vastus medialis relative to vastus lateralis, during the balance test or during the step up task (Mann Whitney U test all p> 0.05). We did not find any difference in the proprioceptive abilities of the two groups. Conclusion: We found no significant difference between the groups in the intensity of muscle contraction of the hamstrings relative to the quadriceps, i.e. no evidence for an imbalance in the patients. However the temporal relation between the two needs further investigation

Purpose: The study was designed to evaluate the biomechanical and neurohistological properties of the infrapatellar fat especially concerning its potential role in the anterior knee pain syndrome. Methods: Isokinetic knee extension from 120 of flexion to full extension was simulated on 10 human knee cadaver specimens (6 male, 4 female, average age at death 44 years). Joint kinematics was evaluated by ultrasound sensors (CMS 100TM, Zebris, Isny, Germany), and retro-patellar contact pressure was measured using a thin-film resistive ink pressure system (K-ScanTM 4000, Tekscan, Boston). The infrapatellar tissue pressure was analyzed using a closed sensor cell. The patellar contact pressure was measured before and after resection of the infrapatellar fat pad. The distribution of nerve fibres in the infrapatellar fat pad was assed immunohistologically in a second part of the study. Results: Infrapatellar tissue pressure significantly increased during knee extension < 20 and flexion > 100 ranging from 343 (223) mbar at O- to 60 (64) mbar at 60 of flexion. Total resection of the infrapatellar fat pad resulted in a significant decrease in tibial external rotation of 3° in full knee extension (p=0.011), combined with a significant medial translation of the patella between 29 and 69° knee flexion (p=0.017 to 0.028). Retropatellar contact pressure was significantly (p< 0.05) reduced at all flexion angles, at 120° knee flexion more than in full knee extension. Studying all the detectable nerves present in 50 fields (x200 objective) we found an average of 6.4 substance-P- (25%) of a total of 24.7 nerve fibres in the infrapatellar fat pad. There was a significantly (p< 0.01) higher number of substance-P-fibers (24.4 (28%) of 105.7) in the superficial synovial tissue. The number of S-100-fibers was significantly (p< 0.05) higher in the central and lateral part of the fat pad. Conclusions: Based on these results, we conclude that resection of the infrapatellar fat pad could potentially reduce clinical symptoms in the anterior knee pain syndrome, and that, contrary to commonly believed, the infrapatellar fat pad may have a biomechanical function and play a role in the anterior knee pain syndrome

Postoperative anterior knee pain was evaluated in a consecutive series of 138 knees in 108 patients with rheumatoid arthritis treated by total knee replacement with Mark I Insall-Burstein prostheses. No knee had primary patellar resurfacing, and in the 119 knees followed up for a mean of 63.9 months, none had secondary resurfacing. Anterior knee pain was absent in 87 knees (73%), mild in 16 (13.5%) and moderate or severe in 16 (13.5%). The height of the patella above the prosthetic joint line was the only variable which was directly related to the incidence of anterior knee pain. The sensitivity and specificity of patellar height measurements for identifying patients with or without pain were derived. From these data, a selective policy of resurfacing the patella in those at risk was adopted. Choosing a patellar height of 15 mm or less, patellar resurfacing could be avoided in 80% of patients likely to have no pain, and the patella could be resurfaced in 65% of those likely to have anterior knee pain

PURPOSES. Previous studies on patella-femoral morphology have suggested patella maltracking plays an important part in the aetiology but there had been no studies correlating maltracking with articular cartilage change. METHODS. We studied 147 consecutive patients (294 knees) aged between 10 and 63 presenting with anterior knee pain. All underwent MRI tracking scan of their knees as part of the routine investigations. We analysed the prevalence of maltracking with respect to gender, laterality and age groups, as well as patello-femoral articular cartilage changes. RESULTS. 52% of patients were found to have maltracking, of which 75% were bilateral. Furthermore, 66% of patients with maltracking had radiological evidence of patellar articular cartilage changes, corresponding to 61% of 294 knees examined. While majority of these occur at lateral facet, a proportion of medial facet changes (16%) is also seen. More significantly, while 25% of knees from patients with maltracking under the age of 20 are found to have changes on the patella cartilage, this increases to 93% by the age of 50 or above, with step-wise increment per decade of age (p<0.01). CONCLUSION. Our results demonstrate a strong correlation between anterior knee pain symptoms, patella maltracking and changes in patello-femoral joint cartilages of varying severity. This has implications on the management of these patients and would suggest early correction of maltracking is indicated to prevent deterioration in the patello-femoral joint

To assess the prevalence of anterior knee pain more than 5 years after closed intramedullary nailing of the tibia and evaluate the long-term socioeconomic impact of this complication in terms of knee function and employment. A retrospective, cohort study of 298 consecutive tibial intramedullary nailings in 295 patients. Minimum follow-up was 5 years and patients were assessed using a questionnaire and the Lysholm knee score. 26 patients are known to have died, 22 patients, greater than 60 years at the tune of their injury, were excluded, Thus, 251 knees in 248 patients were available for review. The mean age at follow-up was 40. 8 years. The male to female ratio was SA:1 and mean follow-up was 7. 9 years. Anterior knee sensory disturbance was reported by 58% of patients. This interfered with activities of daily living (ADLs) in 29%, work in 25% and sport in 37%. Anterior knee pain was reported by 47% of patients. This interfered with ADLs in 37%, work in 36% and sport in 57%, Anterior knee pain was present all the time in 4%, often in 12%, sometimes in 27%, rarely in 21% and never in 37%, Pain on kneeling was rated on a visual analogue scale as mild in 54%, moderate in 34% and severe 12%. AKP improved with time in 73% patients and became worse in 4%. The Lysholm score rated 4 1 % knees as excellent, 19% as good, 26% as fair and 14% as poor. 86% of patients have been able to return to work, 9% are currently unemployed and 5% disabled. The presence of anterior knee pain was felt by the patient to prevent return to previous work in 10%. Anterior knee pain persists in 47% of patients after intramedullary nailing of the tibia- There is some decrease in symptoms with time and the majority of patients are able to return to work and activities of daily living. However, anterior knee pain causes significant disability in a small number and all patients should be warned of this problem prior to surgery

Purpose of the study: To develop a new treatment algorithm for patients with chronic anterior knee pain based on kinematic patella tracking MR imaging. Methods and Results: Patients with anterior knee pain of more than one year duration and not responding to non-operative treatment, underwent kinematic MRI study. The provocative test was performed with the conventional MRI scanner and the patient extending the knee against resistance, the resistance provided by inflated beach ball. A retrospective analysis was done of first seventy patients, who had undergone this scanning technique. On the imaging films, four measurements were made. They were patella subluxation, tilt, cartilage thickness and the Tibial Tubercle Trochlear distance (TTD). Patellar subluxation was classified as mild, moderate and severe. We found that a Tibial Tubercle Trochlea distance of 18mm had a specifity of 100% and a sensitivity of 89% for severe maltracking. Conclusion: Kinematic MR Imaging is a useful investigation before considering operative treatment for patients with chronic anterior knee pain. Based on our study, we conclude that those patients with moderate lateral maltracking with a TTD< 18 mm should be offered lateral release and those with severe maltracking and TTD> 18mm should have a tibial tubercle transfer, in addition to lateral release

Purpose of the study: To develop a new treatment algorithm for patients with chronic anterior knee pain based on kinematic patella tracking MR imaging. Methods and Results: Patients with anterior knee pain of more than one year duration and not responding to non-operative treatment, underwent kinematic MRI study. The provocative test was performed with the conventional MRI scanner and the patient extending the knee against resistance, the resistance provided by inflated beach ball. A retrospective analysis was done of first seventy patients, who had undergone this scanning technique. On the imaging films, four measurements were made. They were patella subluxation, tilt, cartilage thickness and the Tibial Tubercle Trochlear distance (TTD). Patellar subluxation was classified as mild, moderate and severe. We found that a Tibial Tubercle Trochlea distance of 18mm had a specifity of 100% and a sensitivity of 89% for severe maltracking. Conclusion: Kinematic MR Imaging is a useful investigation before considering operative treatment for patients with chronic anterior knee pain. Based on our study, we conclude that those patients with moderate lateral maltracking with a TTD< 18 mm should be offered lateral release and those with severe maltracking and TTD> 18mm should have a tibial tubercle transfer, in addition to lateral release

Femoral component fracture is a rarely reported but devastating complication of total knee arthroplasty. It has occurred most frequently with Whiteside Ortholoc II replacements uncemented knee replacements. Presentation may be with acute pain, progressive pain or returning deformity. It occurs more commonly in the medial condyle of the femoral component. It is rarely seen in cemented replacements. All currently available literature describing fractures of condylar replacements, both cemented and uncemented. Predisposing factors include varus deformity either pre or post operatively. The mechanism of failure is thought to be failure of the infiltration of bone into the replacement. This is often due to polyethylene wear or metallosis causing abnormal tissue reaction with or without osteolysis. We present the case of a fractured Press Fit Condylar (PFC) cemented implant (DePuy, Johnson&Johnson, Raynham, Massachusettes, USA) affecting the medial condyle. To our knowledge this is only the third reported case of fracture in a PFC implant, and the first in a cemented PFC implant. Our patient was a 64 year old male who presented with unresolving knee pain post total knee arthroplasty, caused by fatigue fracture of the medial condyle of the femoral component. This was identified as loosening on plain radiographs and replaced with a revision prosthesis with a good post operative result. Given our aging population and with the increase of joint arthroplasty, this case sheds light on a potentially under recognised and increasingly important cause of knee pain following arthroplasty

Out of a total of 623 patients who, over a ten-year period, underwent primary total knee replacement (TKR) without patellar resurfacing, 20 underwent secondary resurfacing for chronic anterior knee pain. They were evaluated pre- and postoperatively using the clinical and radiological American Knee Society score. The mean follow-up was 36.1 months (12 to 104). The mean knee score improved from 46.7 to 62.2 points and the mean functional score from 44.7 to 52.2 points. Only 44.4% of the patients, however, reported some improvement; the remainder reported no change or deterioration. The radiographic alignment of the TKR did not influence the outcome of secondary resurfacing of the patella. Complications were noted in six of the 20 patients including fracture and instability of the patella and loss of movement. Anterior knee pain after TKR remains difficult to manage. Secondary resurfacing of the patella is not advocated in all patients since it may increase patient dissatisfaction and hasten revision

Anterior knee pain after total knee arthroplasty (TKA) occurs in 5% to 30% of patients whether or not the patella has been resurfaced. We retrospectively reviewed our patients, none of whom underwent patellar resurfacing. Only 2% had anterior knee pain, none requiring revision surgery. Our follow-up was between two and five years. We paid particular attention to removing osteophytes and conducting a thorough peripatellar synovectomy and a circumpatellar cautery denervation. Our results compare favourably to those in the literature, whether or not the patellae were resurfaced. We conclude that patellar resurfacing in TKA is unnecessary when careful attention is paid to the peripatellar tissues

The purpose of this study was to evaluate the influence of trochlear design in total knee replacement with and without patellar resurfacing. Methods and Results: In 1992 a trial was set up, including all patients undergoing primary PFC (Johnson & Johnson) total knee replacement. Patients were randomised to either patellar resurfacing or retention. The patients were assessed using the American Knee Society rating, a clinical anterior knee pain score and BOA patient satisfaction score. Assessment was performed without knowing whether the patella had been resurfaced. In July 1998 we began using the PFC Sigma. This incorporates a deeper trochlear groove with a 5° valgus angle. We compared the results for the two types of prosthesis. In the PFC group there were 474 knees in 390 patients. Follow-up was from 2 to 9 years (mean 5.5 years). The overall prevalence of anterior knee pain) was 25.1% (58 knees) and 5.3% (13 knees) in the non-resurfaced group (n=231) versus the resurfaced group (n=243) respectively. Anterior knee pain became apparent in all cases within 18 months. In the PFC sigma group there were 67 knees in 62 patients. Follow-up was from 18 months to 3 years (mean 2 years). The incidence of anterior knee pain was 0 in the resurfaced group (n=30) versus 37.8% (14 knees) in the non-resurfaced group (n=37). Knee scores were lower in the non-resurfaced groups for each prosthesis. Conclusion: The prevalence of anterior knee pain was significantly higher in knees with non-resurfacing of the patella. The asymmetrical, deeper femoral groove improves anterior knee pain with the resurfaced patella but may contribute to it if not resurfaced. We recommend patellar resurfacing in all cases where technically possible

Introduction and Aims: Many authors believe that patellar resurfacing decreases the incidence of anterior knee pain. We analysed the result of 150 of our own patients. Method: Over the past four years we performed 150 total knee arthroplasties. None of the patellae were resurfaced, osteophytes were carefully removed, the patellae debrided, a thorough peri-patellar synovectomy and circumpatellar cautery denervation performed. All patients were examined by a consultant and a registrar to determine the site of any pain complaint. If there was any controversy a third surgeon was consulted. Results: No patient had pain severe enough to warrant revision surgery. Only two patients had anterior knee pain, and in neither was it marked. Conclusion: We do not know whether our favourable results are attributable to the patellar management, or due to the prosthesis used. We concede that a prospective randomised trial is necessary to determine this, but with such a low incidence of patellar complications we feel this is not ethically justified

Anterior knee pain (AKP) is the commonest complication of total knee arthroplasty (TKA). This study aims to assess whether sagittal femoral component position is an independent predictor of AKP after cruciate retaining single radius TKA without primary patellofemoral resurfacing. From a prospective cohort of 297 consecutive TKAs, 73 (25%) patients reported AKP and 89 (30%) reported no pain at 10 years. Patients were assessed pre-operatively and at 1, 5 and 10 years using the short form 12 and Oxford Knee Score (OKS). Variables assessed included demographic data, indication, reoperation, patella resurfacing, and radiographic criteria. Patients with AKP (mean age 67.0 (38–82), 48 (66%) female) had mean Visual Analogue Scale (VAS) Pain scores of 34.3 (range 5–100). VAS scores were 0 in patients with no pain (mean age 66.5 (41–82), 60 (67%) female). Femoral component flexion (FCF), anterior femoral offset ratio, and medial proximal tibial angle all differed significantly between patients with AKP and no pain (p<0.001), p=0.007, p=0.009, respectively). All PROMs were worse in the AKP group at 10 years (p<0.05). OKSs were worse from 1 year (p<0.05). Multivariate analysis confirmed FCF and Insall ratio <0.8 as independent predictors of AKP (R. 2. = 0.263). Extension of ≥0.5° predicted AKP with 87% sensitivity. AKP affects 25% of patients following single radius cruciate retaining TKA, resulting in inferior patient-reported outcome measures at 10 years. Sagittal plane positioning and alignment of the femoral component are important determinants of long-term AKP with femoral component extension being a major risk factor

Idiopathic anterior knee pain (AKP) is common in adolescents and young adults. Most believe that the origin of the problem lies in the patello-femoral joint. Hamstring tightness has also been attributed as an important cause. The aim of our study was to compare biometric parameters in patients with idiopathic AKP and controls. We also wanted to assess whether there was a difference in the relative electromyographic (EMG) onset times of the medial and lateral hamstrings. We prospectively recruited patients with idiopathic anterior knee pain in the age group 11 to 25. Patients, but not the control population, had AP, lateral and skyline radiographs taken to rule out other pathology. We had 34 patients (60 knees) with a minimum one year follow up. There was no difference in the symptoms of patients who attended physiotherapy as compared to those who did not. Patients with knee pain had significantly more hip external rotation (63 deg) as compared to the control (47 deg) group (p=0.001). Patients also had significantly more hamstring tightness (p=0.04). Surface EMG was recorded (17 patients and controls each) from the medial and lateral hamstrings during 3 repetitions of a maximal voluntary isometric contraction exercise with the knee at 45° of flexion. The lateral hamstrings contracted 48.7 m.sec earlier than the medial hamstrings in patients as compared to controls. AKP is a multifactorial and self-limiting disorder. Earlier contraction of the lateral hamstrings may cause tibial external rotation and contribute to the symptoms. Our data suggests that physiotherapy did not significantly alter the course of the condition. We believe that increased hip external rotation may contribute to the symptoms by increasing medial facet stress

The accurate diagnosis of periprosthetic infection poses a challenge to the clinician and the imaging specialist alike. In recent years, FDG-PET imaging has shown great promise in the evaluation of occult infection at various anatomic sites. The purpose of this investigation was to determine the accuracy of FDG-PET imaging in diagnosing periprosthetic infection associated with total knee arthroplasty. Sixty eight painful knee prostheses were referred for further evaluation with FDG-PET imaging. Approximately 60 minutes after the intravenous administration of FDG, PET images of both knees were acquired and interpreted by experienced nuclear medicine physicians. PET images demonstrating increased FDG activity at the bone-prosthesis interface were considered infected. Final diagnosis was made on the basis of surgical findings, histopathology, and clinical follow-up. FDG-PET correctly diagnosed 19 of the 22 infected cases for a calculated sensitivity of 86.4% (19/22). FDG-PET correctly predicted the absence of infection in 38 of 46 aseptic knee prostheses for a calculated specificity of 82.6% (38/46). The negative and positive predictive values for FDG-PET imaging in this setting were 92.7% (38/41) and 70.4% (19/27), respectively. The overall accuracy of FDG-PET imaging was 83.8% (57/68). FDG-PET was indeterminate in three cases which were not included in this analysis. These results demonstrate that FDG-PET is a useful diagnostic tool for the evaluation of possible infection associated with knee arthroplasty. Considering the large number of subjects who undergo total knee arthroplasty and the sizable fraction who develop complications following surgery, the impact of FDG-PET imaging could be substantial. Examination of a larger number of patients with painful knee prostheses will further clarify the merit of this powerful technique in this clinical setting

Aims: To report the outcome of secondary patellar resurfacing in patients with chronic anterior knee pain following primary total knee replacement. Methods: A total of twenty patients identified over a 10-year period from 623 patients managed without patellar replacement during primary knee arthroplasty were included and evaluated pre and postoperatively using the American Knee Society (AKS) score, as well as by radiological analysis. Results: The mean follow up was 36.1 months (range 12–104 months). The mean knee score improved from 46.7 to 62.2 points while the mean functional score increased from 44.7 to 52.2 points. Only 44.5% of the patients reported some improvement whereas the remaining reported no change or deterioration. Postoperative radiographic alignment of the primary knee arthroplasty did not influence outcome of secondary patellar resurfacing. Complications were noted in 6 of the 20 patients including patella fracture, patella instability and loss of a range of movement. Conclusions: Anterior knee pain following knee arthroplasty remains a difficult condition to manage and secondary resurfacing of the patella is clearly not to be advocated in all patients since it may well increase patient dissatisfaction and hasten revision

Many authors believe that patellar resurfacing decreases the incidence of anterior knee pain. We analysed the results of 98 of our own patients (103 knees). Over the past two years, we performed total knee arthroplasty on 23 men (one bilateral) and 75 women (four bilateral). None of the patellae were replaced, but we carefully removed osteophytes, debrided the patella, and performed a thorough peripatellar synovectomy and circumpatellar cautery denervation. All patients on our database were telephoned, and those who reported pain were examined independently by a consultant and a registrar. If there was any controversy about the site of the pain, a third surgeon saw the patient. No patient had pain severe enough to warrant revision surgery. Only two (2%) had anterior knee pain, and in neither of them was it marked. We do not know whether our favourable results are attributable to the peripatellar synovectomy and/or circumpatellar cautery denervation. While we concede that a control study of patients who have undergone patellar resurfacing might be necessary before a firm conclusion can be drawn, we question whether, with such a low incidence of patellar problems, this is ethically justifiable

Introduction. Anterior knee pain (AKP) is a recognized cause of patient's dissatisfaction after total knee arthroplasty. Potential implant/technique related contributors to AKP are patellofemoral maltracking, trochlear geometry, femoral malrotation, patellar tilt and overstuffing. The primary aim of this prospective, matched pair study was to assess the safety, efficacy and performance of an anatomic patella and its effect on AKP in in a matched pair analysis. Material and Methods. Between July 2012 and May 2013, 55 consecutive posterior stabilized cemented Attune TKAs (Depuy) were matched to the PFC Sigma group based on age, gender, and body mass index (BMI). All surgeries were performed via medial parapatellar approach with patellar resurfacing. Clinical and radiographic analysis was performed prospectively with minimum 6 month follow-up. Radiographic measurements included overall limb alignment, anterior offset, posterior offset, joint line, patellar thickness, patellar tilt and patellar displacement by two independent observers. Results. The mean functional outcomes were similar in both groups. AKP incidence between Attune and PFC was statistically insignificant (3.6% and 3.8%). Radiographic analysis revealed no mal-alignment, or osteolysis. No complications such as infection, patellar fracture, subluxation or dislocations were observed. Discussion. Attune knee design demonstrates excellent short-term safety and efficacy. At minimum 6-month follow-up, anatomical patella with shows less AKP than single radius patella design. Longer follow-up is required to assess functional outcome this design

Query: Persistent complaints following implantation of a knee prosthesis are often a problem which is hard to overcome. On the one hand, general diagnostics do not reveal the cause of the complaints, on the other, pain symptoms in connection with deficient patella control cannot always be attributed to insufficient equilibrium of the soft tissues. In this prospective study, the rotation of the components was examined in connection with the pain described by 49 patients. Method: The rotation of the prosthesis components was examined by means of axial CT scans in 49 patients with the complaint symptoms described above and without signs of loosening or malpositioning at the frontal or sagittal level. The results were set in relation to clinical symptoms, the Knee Society Score and a VAS. Results: A direct relationship was found between the extent of the added inner rotation malpositioning of the components and a deteriorated Knee Score. No difference in the pain score in dependence on the extent of improper implantation could be observed. Incorrect tibial rotation was responsible in particular for patellar lateralization, subluxation or tipping. Conclusion: The correlation between inner rotation malpositioning and deficient patellar control or signs of instability underlines the importance of intraoperative rotation adjustment in the prevention of knee pain. In unclear knee pain following knee endoprosthesis implantation, performance of a CT to determine the component rotation is indicated. If there is a rotation malpositioning, correction in a revision procedure should be considered

7–20 % of the patients with a total knee arthroplasty (TKA) are dissatisfied without an indication for revision. Therapeutic options for this patient population with mostly a lack of quadriceps strength are limited. The purpose of this study is to evaluate the effect of six weeks low load resistance training with blood flow restriction (BFR) on the clinical outcome in these unhappy TKA patients.

Thirty-one unhappy TKA patients (of the scheduled fifty patients) without mechanical failure were included in this prospective study since 2022. The patients participate in a supervised resistance training combined with BFR, two times a week during nine weeks. Patients were evaluated by the Knee Osteoarthritis Outcome Score (KOOS), Knee Society Score: satisfaction (KSSs) and the Pain Catastrophizing Scale (PCS). Functionality was tested using the Six Minute Walk Test (6MWT) and the 30-Second Chair Stand Test (30CST). Follow-up took place at six weeks, three months and six months after the start.

Six weeks training with BFR provided statistically significant improvements in all the KOOS subscales compared to the baseline, especially for symptoms (55.1 (±15.4) versus 48.0 (±16.5); p<0.001), activities in daily living (50.3 (±21.1) versus 43.7 (±17.2); p<0.00) and quality of life (24.6 (±18.5) versus 17.3 (±13.0); p<0.001). The PCS reduced from 27.4 (±11.0) to 23.2 (±11.4) at six weeks (p<0.01), whereas the KSSs increased from 11.8 (±6.5) to 14.9 (±7.6) (p=0.021). Both the 6MWT and the 30CST improved statistically significant from respectively 319.7 (±15.0) to 341.6m (±106.5) (p<0.01) and 8.6 (±3.9) to 9.3 times (±4.5) (p<0.01).

Blood flow restriction appears to enhance the quality of life and functional performance of unhappy TKA patients. Based on these preliminary results, BFR seems to be a promising and valuable alternative for these TKA patients with limited therapeutic options.

Purpose of Study: To further study a group of patients with characteristic features presenting with significant, perisistent, and seemingly hard to diagnose and so treat, knee pain. Methods/Results: 16 cases were collected. The was no association with age. 8 cases were sent as a second opinion. Causation: 7 cases:direct trauma [5: associated with MCL tears (1 chronic overload from triple-jump),1:a blow to front of knee, 1:chronic from kneeling]. 4 cases: Knee replacement- related [irritation from osteophyte 1; implant-related 3]. 3 cases: irritation from medial meniscal sutures [2: Fast-Fix; 1: in:out]. 1 case: surgery induced neuroma in arthrotomy wound. 1 case: irritation by an enlarging cyst. In all cases the time to make the diagnosis was prolonged. All had pain, which on close questioning was ‘neuritic’ [burning] in approximately 2/3. It was exceedingly well localized in all. Altered sensation in the appropriate distribution was noted by the patient in 3 cases, but shown in 5 cases on examination. A positive Tinel test was present in all cases. In approximately half of cases ultrasound plus diagnostic injection of local anaesthetic [+/− steroid] was useful. However 15 of the 16 came to surgery in which a neurolysis or removal of neuroma, in 3 cases, [all confirmed on histology] was undertaken plus the underlying causative factor dealt with eg excision of osteophyte or scar. One case settled [90% better according to patient] after ultrasound-guided injection of a prepatellar bursa which was irritating the infrapatellar branch of the nerve. Of the 15 who had had surgery 12 had complete resolution of symptoms. Conclusion: Although a relatively uncommon this scenario is worth considering as a cause of significant morbidity, with a good outcome from treatment in most cases. The presentation is of persistent very well localized troubling pain with marked tenderness, and a positive Tinel test

In years past, the most common reason for revision following knee replacement was polyethylene wear. A more recent study indicates that polyethylene wear is relatively uncommon as a cause for total knee revision counting for only 10% or fewer of revisions. The most common reason for revision currently is aseptic loosening followed closely by instability and infection. The time to revision was surprisingly short. In a recent series only 30% of knees were greater than 5 years from surgery at the time of revision. The most common time interval was less than 2 years. This is likely because of the higher incidence of infection and instability that occurs most commonly at a relatively early time frame. Evaluation of a painful total knee should take into account these findings. All total knees that are painful within 5 years of surgery should be assumed to be infected until proven otherwise. Therefore, virtually all should be aspirated for cell count, differential, and culture. Alpha-defensin is also available in cases in which a patient may have been on antibiotics within a month or less, as well as cases in which diagnosis is a challenge for some reason. Instability can be diagnosed with physical exam focusing on mid-flexion instability which can be usually determined with the patient seated and the knee in mid-flexion, with the foot flat on the floor at which point sagittal plane laxity can be discerned. This is also frequently associated with symptoms of giving way and recurring effusions and difficulty descending stairs. A new phenomenon of tibial de-bonding has been described, which can be a challenge to diagnose. Radiographs can appear normal when loosening occurs between the implant and the cement mantle. This seems to be more common with the use of higher viscosity cement. Obviously this is technique dependent since good results have been reported with the use of high viscosity cement. Component malposition can cause stiffness and pain and relatively good results have been reported by component revision when malrotation has been confirmed with CT scan. When infection, instability and loosening are not present, extra-articular causes should be ruled out including lumbar spine, vascular compromise, complex regional pain syndromes and fibromyalgia, and peri-articular causes such as bursitis, tendonitis, tendon impingement among others. One of the most common causes of pain following total knee is unrealistic patient expectations. Performing total knee replacement in early stages of arthritis with only mild to moderate symptoms and radiographic changes has been associated with persistent pain and dissatisfaction. It may be prudent to obtain the immediate preoperative x-rays to determine if early intervention was undertaken and patients have otherwise normal appearing total knee x-rays and a negative work up. A recent study indicated that this was likely a cause or a major contributing factor to persistent pain following otherwise a well performed knee replacement. A national multicenter study of the appropriateness of indications for TKA also indicated that early intervention was a major cause of persistent pain, dissatisfaction, and failure to improve following total knee replacement.

The aim was to compare anterior knee pain (AKP) felt before, and after hamstrings (HS, n = 65) and bone-patellar tendon- bone [B-PT-B, n = 94] ACL reconstructions. The same questionnaire (modified from Shelbourne et al 1997) was answered by patients before, and at least 12 months after surgery. Questions covered five main categories of pain ie. during prolonged sitting, stair climbing, kneeling, sport or vigorous activity, and ADL. There was no statistical difference in the two groups in overall AKP scores before surgery. After surgery, there were improvements in this overall score in both groups, but the improvement was statistically greater in the HS group (p = 0.02). Analysis of the five different pain categories showed no significant difference in the improvements in sitting, sport or ADL. In both climbing stairs (p = 0.009), and kneeling (p = 0.02) there were significantly greater improvements in the HS group. The majority of patients had AKP before surgery. Surgery improved pain levels in both HS and B-PT-B groups, but there was statistically significant greater improvements in overall AKP scores, and the scores for climbing stairs and kneeling in the HS group

We report a rare case of an intracortical chondroma in the region of the medial femoral condyle of the femur extending into the femoral sulcus and the patellofemoral joint.A sixteen year old Asian boy presented with repeated episodes of right sided anterior knee pain and giving way over a three year period. The patient had been treated previously for multiple bony swellings at another hospital and a diagnosis of multiple enchondromatosis had been made. Examination revealed that the patellofemoral compression test was positive with fullness over the medial eminence of the femur in the region of the trochlear groove.Pre-operative X-rays and MRI scan showed the presence of an intracortical lesion over the medial femoral condyle extending into the femoral sulcus. The lesion demonstrated intermediate signal intensity on T1 and high intensity on T2 weighted images with variable low signal intensity foci due to the presence of a calcified matrix. The patient underwent arthroscopic examination. An intra-articular lesion (2cmx 3cm.) was identified and excised through a mini-arthrotomy. The lesion was entirely intra-articular arising from the medial femoral condyle proximal to the femoral sulcus, extending partially into the supra-patellar pouch. Histopathological examination confirmed the presence of a low grade cartilaginous neoplasm best diagnosed as an atypical chondroma. At a two year follow up appointment the patient was found to be asymptomatic with no evidence of radiological recurrence. Although there have been several reports of periosteal chondromas developing around the knee the majority deal with soft tissue chondromas in para-articular locations or intra-cortical tumours in extra-articular regions. Our tumour is unique due to its intra-articular and intracortical location. A detailed review of the literature of this rare tumour is presented with a pictorial presentation of the case including arthroscopic radiological and histopathological findings

Purpose. Anterior knee pain has been relieved by resection of the infrapatellar plica (IPP). The question is: How? The hypothesis is: the IPP acts as an intra-articular ligament, a mechanical link between the forces of knee motion, the fat pad (FP) and the distal femur, holding the FP captive through the arc of motion. Release of the IPP severs this link, allowing the highly innervated FP to move freely. This may allow any underlying pathologic process to heal. Method. Anatomic dissection: In 12 knees, the extensor apparatus was released from the femur and retracted distally allowing relationships to be examined. Cadaver studies: Lateral fluoroscopy was used as well as direct arthroscopic visualization to control implantation of tantalum beads or radiographic contrast material in the FP and IPP. The knee was taken through the arc of motion repeatedly. The femoral attachment of the IPP was then released and knee motion repeated. Traction on the extensor apparatus simulated active motion. In-Vivo Study: The IRB approved study of 12 volunteers undergoing planned knee arthroscopy under local anesthesia. Contrast was placed in the FP and IPP under lateral fluoroscopic control. Passive, then active motion then a quads-set manoeuvre was performed. The IPP was resected and knee motion again recorded. Results. Knees without IPP (4) demonstrated FPs that were lobular, with lateral bodies, and a central process. The fibrous synovial layer of the capsule bypassed the FP inserting on the superior aspect of the menisci. Knees with an IPP (8) showed a FP that was covered by fibrous synovium. The fibrous elements of the capsule coalesced on either side of the patellar in folds that merged with the alar folds. These fibrous elements ramified over and through the FP and were continuous with the upper portion of the IPP medially and laterally. Inferiorly the lower portion of the IPP merged with fibrous synovium that attached to the superior aspect of the menisci and the inter-meniscal ligament. The cadaver studies demonstrated that the IPP elongated with FP distortion as the knee approached full extension and flexion, and that the IPP was lax through mid arc. Release of the IPP at the femur eliminated almost all of the distortion through the full arc. The In-Vivo study replicated the cadaver observations for passive and active motion. The quads set manoeuvre caused further distortion of the FP with the patella moving one cm proximally. Release of the IPP eliminated FP distortion. Conclusion. The IPP seems to act as a true ligamentum mucosum. By virtue of its central femoral attachment if captures the FP against the end of the femur, loosely in mid arc, but with distortion of the FP and stretch of the IPP approaching full flexion and extension. This has been demonstrated in both cadavers and in in-vivo for the first time. Any pathologic process affecting the highly innervated FP will likely be improved by removal of the capture effect of the IPP

The true results of revision total knee arthroplasty (TKA) are not fully understood, for a variety of understandable reasons. But it is has been clear for decades that revision without a diagnosis is likely to fail. The evaluation of the problem TKA should be systematic (follow the same scheme every time) and comprehensive (all possibilities should be considered even if one diagnosis seems obvious).

Evaluation begins, as with all of medicine with a list of possible causes: the mechanisms of failure. John Moreland was the first to describe a coherent system which needed only one simple addition to be complete: 1.) Prosthetic joint infection; 2.) Extensor disruption; 3.) Patella and malrotation; 4.) Loose; 5.) Component breakage; 6.) PP fracture; 7.) Poor motion; and 8.) Tibial femoral instability.

Evaluation begins with the history, where 10 questions in particular are useful: 1.) What seems to be the problem? 2.) Was the “knee” ever successful after surgery? If there was never pain relief, is the current pain, the same or different? 3.) Standard pain quality questions - Location, duration, frequency, quality, exacerbating, ameliorating. 4.) Swelling? 5.) Stiffness? 6.) Giving way? 7.) Weakness? 8.) Things “just don't feel right”? 9.) Possible sepsis questions - Fever, chills, sources, primary TKA healing. 10.) Mood, social situation?

The physical exam should cover these ten points: 1.) Active extension; 2.) Rising from chair; 3.) Gait: hip, knee alignment, knee instability; 4.) Hip (internal rotation); 5.) Inspection; 6.) Tenderness; 7.) ROM; 8.) Stability (extension and 30–45 degrees flexion; 9.) Sitting on edge of exam table (knee at 90 degrees); and 10.) Step up on low stool (stair).

Investigations include: 1.) ESR + CRP; 2.) CBC; 3.) HGB- anemia; 4.) Lymphocytes- nutrition; 5.) GGT- alcohol abuse; 6.) Albumen- nutrition; 7.) HbA1c- diabetic control.

Imaging includes: 1.) Single leg weightbearing AP; 2.) Lateral; 3.) Merchant; 4.) Full length (hip-knee-ankle); 5.) AP pelvis; 6.) CT scan; and 7.) (Technitium bone scan).

Aims: The purpose of the study was to determine the distribution and speciþcation of nerve þbers in the infrapatellar fat pad especially concerning nociceptive substance-P þbres. Methods: The infrapatellar fat pad was taken as a fresh specimen out of 21 patients (4 male, 17 female, mean age 69 years) during total knee arthroplasty. It was dissected in þve deþned parts, þxed and embedded in parafþn. Immunohistochemical techniques using antibodies against S-100 protein and substance-P were employed to determine and specify the nerve þbres. Results: Studying all the detectable nerves present in 50 þelds (x200 objective) we found an average of 6,4 substance-P- (25%) of a total of 24,7 nerve þbres in the infrapatellar fat pad. There was a significantly (p< 0,01) higher number of substance-P-þbers (24,4 (28%) of 105,7) in the surfacing synovial tissue. The number of S-100-þbers was signiþcantly (p< 0,05) higher in the central and lateral part of the fat pad. Conclusions: The occurance and distribution of nerve þbres in the infrapatellar fat pad suggests a nociceptive function. A neurohistological role in the anterior knee pain syndrome is assumed

Persistent post-surgical pain remains a problem after knee replacement with some studies reporting up to 20% incidence. Pain is usually felt by those who do not operate to be a monolithic entity. All orthopaedic surgeons know that this is not the case. At its most basic level, pain can be divided into two categories, mechanical and non-mechanical.

Mechanical pain is like the pain of a fresh fracture. If the patient does not move, the pain is less. This type of pain is relieved by opiates. Mechanical pain is seen following knee replacement, but is fortunately becoming less frequent. It is caused by a combination of malrotations and maltranslations, often minor, which on their own would not produce problems. The combination of them, however, may produce a knee in which there is overload of the extensor mechanism or of the medial stabilizing structures. If these minor mechanical problems can be identified, then corrective surgery will help.

Non-mechanical pain is present on a constant basis. It is not significantly worsened by activities. Opiates may make the patient feel better, but they do not change the essential nature of the pain. Non-mechanical pain falls into three broad groups, infection, neuropathic and perceived pain. Infection pain is usually relieved by opiates. Since some of this pain is probably due to pressure, its inclusion in the non-mechanical pain group is questionable, but it is better left there so that the surgeon always considers it. Low grade chronic infection can be extremely difficult to diagnose. Loosening of noncemented knee components is so rare that when it is noted radiologically, infection should be very high on the list of suspicions. The name neuropathic pain suggests that we know much more about it than we do in reality. Causalgia or CRPS-type two is rare following knee replacement. CRPS type one or reflex sympathetic dystrophy probably does exist, but it is probably over-diagnosed especially by the author of this abstract. The optimum treatment I have found is lumbar sympathetic blocks. Perceived pain is the largest group. It does not matter what you tell the patient, some believe a new knee should be like a new car, i.e. you step into it and drive away. The fact that they have to work to make it work is horrifying. Some of this pain is actually mechanical, especially in those with no benefits such as hairstylists. Perceived pain is widespread. The classic treatise on this is Dr. Ian McNabb's book “Backache”. It should be studied by all orthopaedic surgeons, who wish to understand pain complaints.

Any experienced knee surgeon will have his list of red flags or caveats. These are often politically incorrect and this information is transferred to young surgeons, usually in dim bars late at night. I will list only a few. If the patient comes in with a form asking for a disability pension on the first visit. If the patient's mother answers the questions. If the patient comes in taking massive doses of opiates. If the patient is referred to you by a surgeon, who does more knee replacements than you do. There is also the recently described Fern Silverman's syndrome.

Persistent post-surgical pain (PPSP) remains a problem after knee replacement with some studies reporting up to 20% incidence. Pain is usually felt by those who do not operate to be a monolithic entity. All orthopaedic surgeons know that this is not the case. At its most basic level, pain can be divided into two categories, mechanical and non-mechanical.

Mechanical pain is like the pain of a fresh fracture. If the patient does not move, the pain is less. This type of pain is relieved by opiates. Mechanical pain is seen following knee replacement, but is becoming less frequent. It is caused by a combination of malrotations and maltranslations, often minor, which on their own would not produce problems. The combination of them, however, may produce a knee in which there is overload of the extensor mechanism or of the medial stabilizing structures. If these minor mechanical problems can be identified, then corrective surgery will help.

Non-mechanical pain is present on a constant basis. It is not significantly worsened by activities. Opiates may make the patient feel better, but they do not change the essential nature of the pain. Non-mechanical pain falls into three broad groups, infection, neuropathic and perceived pain. Infection pain is usually relieved by opiates. Since some of this pain is probably due to pressure, its inclusion in the non-mechanical pain group is questionable, but it is better left there so that the surgeon always considers it. Low grade chronic infection can be extremely difficult to diagnose. Loosening of noncemented knee components is so rare that when it is noted radiologically, infection should be very high on the list of suspicions. The name neuropathic pain suggests that we know much more about it than we do in reality. Causalgia or CRPS-type two is rare following knee replacement. CRPS-type one or reflex sympathetic dystrophy probably does exist, but it is probably over-diagnosed. The optimum treatment I have found is lumbar sympathetic blocks. Lyrica, Gabapentin and Cymbalta may also help. Perceived pain is the largest group. It does not matter what you tell the patient, some believe a new knee should be like a new car, i.e. you step into it and drive away. The fact that they have to work to make it work is horrifying. Perceived pain is widespread. The classic treatise, Dr. Ian McNabb's book “Backache”, should be studied by all who wish to understand pain complaints.

Any experienced knee surgeon will have his list of red flags or caveats. I will list only a few. If the patient comes in with a form asking for a disability pension on the first visit. If the patient's mother answers the questions. If the patient comes in taking massive doses of opiates. If the patient is referred to you by a surgeon who does more knee replacements than you do.

There are other issues such as good old fibromyalgia, which appears to have gone the way of the dodo. It has been replaced by something equally silly called central sensitization. The theory of central sensitization is that if one has pain somewhere or other for three months or six months or whatever, there are going to be changes in the brain and spinal cord. It then does not matter what happens to the original pain, i.e. whether or not it goes away, the pain will persist because of the changes in the brain, hence, the title of the pain in the brain syndrome. If this theory was correct, we might as well all go home because we have all been wasting our time for the last 30 years because none of our patients would get any better. After all, all of our patients have had pain for a lot longer than three months, many of them have been involved in trauma and sometimes, compensation is at issue. The pain in the brain theory, therefore, sounds about as realistic as the flat earth society or the treatment of Galileo.

The causes of pain after TKA can be local (intra or extra-articular) or referred from a remote source. Local intra-articular causes include prosthetic loosening, infection, aseptic synovitis (wear debris, hemarthrosis, instability, allergy), impingement (bone soft tissue or prosthetic), an un-resurfaced patella and stress fracture of bone or the prosthesis. Some surgeons think that isolated component mal-rotation can be a source of pain, but component mal-rotation is rarely present in the absence of other technical abnormalities.

Local extra-articular causes include pes anserine bursitis, saphenous neuroma/dysasthesias, post-tourniquet dysasthesias, complex regional pain syndrome and vascular claudication.

Referred pain is most often from an arthritic hip or radicular pain from a spinal source. Patients with fibromyalgia can have persistent pain following their knee arthroplasty and should be warned of this possibility.

Evaluation of the patient includes a history, physical exam, joint aspiration and plain radiographs. In selected patients, an anesthetic joint injection, bone scan, CT scan or MRI with metal subtraction may be helpful in the diagnosis. The joint aspiration should include a CBC and differential as well as an aerobic and anaerobic culture. Fungal and TB cultures are sometimes indicated.

Re-operation for pain of unknown etiology following TKA is unlikely to yield an excellent result and both surgeons and patients should be aware of this probability.

Persistent post-surgical pain (PPSP) remains a problem after knee replacement with some studies reporting up to 20% incidence. At its most basic level, pain can be divided into two categories, mechanical and non-mechanical.

Mechanical pain is like the pain of a fresh fracture. If the patient does not move, the pain is less. This type of pain is relieved by opiates. Mechanical pain is seen following knee replacement, but is fortunately becoming less frequent. It is caused by a combination of malrotations and maltranslations, often minor, which on their own would not produce problems. The combination of them, however, may produce a knee in which there is overload of the extensor mechanism or of the medial stabilizing structures. If these minor mechanical problems can be identified, then corrective surgery will help.

Non-mechanical pain is present on a constant basis. It is not significantly worsened by activities. Opiates may make the patient feel better, but they do not change the essential nature of the pain. Non-mechanical pain falls into three broad groups, infection, neuropathic and perceived pain.

Infection pain is usually relieved by opiates. Since some of this pain is probably due to pressure, its inclusion in the non-mechanical pain group is questionable, but it is better left there so that the surgeon always considers it. Low grade chronic infection can be extremely difficult to diagnose. Loosening of noncemented knee components is so rare that when it is noted radiologically, infection should be very high on the list of suspicions.

The name neurogenic pain suggests that we know much more about it than we do in reality. Causalgia or CRPS-type two is rare following knee replacement. CRPS type one or reflex sympathetic dystrophy probably does exist, but it is probably over-diagnosed especially by the author of this abstract. The optimum treatment I have found is lumbar sympathetic blocks. Lyrica, Gabapentin and Cymbalta may also help.

Perceived pain is the largest group. It does not matter what you tell patient, some believe a new knee should be like a new car, i.e. you step into it and drive away. The fact that they have to work to make it work is horrifying. Some of this pain is actually mechanical, especially in those with no benefits such as hairstylists. Perceived pain is widespread. The classic treatment on this is Dr. Ian McNabb's book “Backache”. It should be studied by all orthopaedic surgeons, who wish to understand pain complaints.

There are other issues such as good old fibromyalgia, which appears to have gone the way of the dodo. It has been replaced by something equally silly called central sensitization. The theory of central sensitization is that if one has pain somewhere or other for three months or six months or whatever, there are going to be changes in the brain and spinal cord. It then does not matter what happens to the original pain, i.e. whether or not it goes away, the pain will persist because of the changes in the brain, hence, the title of the pain in the brain syndrome.

If this theory was correct, we might as well all go home because we have all been wasting our time for the last 30 years because none of our patients would get any better. After all, all of our patients have had pain for a lot longer than three months, many of them have been involved in trauma and sometimes, compensation is at issue. The pain in the brain theory, therefore, sounds about as realistic as the flat earth society or the treatment of Galileo.

The incidence of pain postoperative total knee replacement runs somewhere between 2 and 4% and is related initially to infections, patellar subluxation or dislocation, fractures, collapse, extensor mechanism rupture, referred pain, and reflex sympathetic dystrophy. Causes for pain after six months is usually associated with infection, loosening, instability, fractures, and referred pain. Trying to understand what causes the problem helps us to be able to evaluate the patient with postoperative pain and offer a resolution.

1. Double osteotomy was performed on 1 50 knees between 1961 and 1969. The first fifty-seven cases were assessed independently.

2. The operation of osteotomy of the upper end of the tibia and the lower end of the femur is described. it is emphasised that the osteotomy sites are close to the bone ends and well within the cancellous expansion.

3. The indications for the operation are pain and loss of function in a mobile arthritic knee joint.

4. Flexion of the knee is important during the operation to allow the popliteal artery to be moved away from bone. Arteriograms at necropsy show the danger of damaging the popliteal artery when the knee is extended.

5. The operation appears to be equally effective in osteoarthritis and rheumatoid arthritis. The proliferated synovium of the active rheumatoid knee regresses rapidly following operation.

6. The operation has resulted in relief of pain and increase in function in many knees which had no deformity. When a deformity did exist before operation recurrence of the deformity did not appear to influence the result.

7. The cause of relief of symptoms after osteotomy is not known, and it is suggested that answers to the following questions should be sought: Why are some arthritic knees painful and some not ? Why does physiotherapy relieve pain ? Why does osteotomy relieve pain? Why is double osteotomy followed by regression of synovial proliferation ? Why does osteotomy sometimes fail ? Would osteotomy of one bone (tibia or femur) be sufficient?

We report the largest multicentre series analysing the use of bone scans investigating painful post-operative Total Knee Replacements (TKR). We questioned the usefulness of reported scintigraphic abnormalities, and how often this changed subsequent management. 127 three-phase bone-scans were performed during a two-year period. Early and late flow phases were objectively classified. Reported incidences of infection and loosening were determined. Reports were subjectively summarised and objectively analysed to establish the usefulness of this investigation. Eight cases were excluded.

Scans were classified as: 33% (39) normal, 53% (63) as possibly abnormal, 6% (7) probably abnormal, and 8% (10) as definitely abnormal. Thirteen patients (11%) underwent revision TKR surgery. Intra-operative analysis revealed loosening of one femoral component, and massive metallosis of the patella in another. Cultures were negative in all cases. The sensitivity and specificity of a definitely abnormal investigation in predicting need for revision surgery was 23% and 82% (respectively). High instances of ambiguously reported abnormalities were observed.

This investigation has no role to play in the routine investigation of a painful TKR. It is unnecessary in investigation of periprosthetic infection and should not be used in a routine assessment of a painful TKR. If used it should be limited until an experienced revision surgeon has made a full assessment.

The purpose of this study was to provide an anatomical explanation for the presence of medial proximal tibial pain in patients with patellar mal-tracking without identifiable medial tibio-femoral compartment or proximal tibial pathology.

Using cadaveric dissection we were consistently able to identify a connection between the medial patella and the medial proximal tibia including the medial hamstrings and the posterior oblique expansion. This connection is independent of the inferior patello-tibial ligament and has not previously been described in either anatomical or orthopaedic literature. The dimensions of this medial patello-tibial connection were measured using a digital microscribe. This technique also facilitated the creation of a three dimensional virtual representation of the patello-tibial connection.

In the clinical setting, patients presenting with medial proximal tibial pain who had patellar mal-tracking as identified by clinical examination and merchant radiographs underwent MRI scanning of the knee to exclude any intraarticular or proximal tibial pathology. In those patients with patellar mal-tracking that had no evidence of proximal tibial or medial compartment pathology identified, we were able to correlate the MRI finding of oedema based at the proximal medial aspect of the tibia with the cadaveric dissection findings mentioned previously. In such cases we would recommend that treatment of the medial proximal tibial pain should focus on managing the primary pathology of patella mal-tracking.

In conclusion we present a newly identified medial patello-tibial ligamentous complex that can explain the presence of medial proximal tibial pain in patients with patellar mal-tracking and no other proximal tibial or medial compartment pathology.

Tibial and femoral deformities might cause patellofemoral problems, but they do not have to be modified every time to obtain good results. We have evaluated external tibial rotation characterised by an external tibial deformity in varus, worsening in parallel feet position. In these patients the only surgical treatment is tibial osteotomy, justified by a positive effect on the knee joint mechanics. From 1990 to 2002 we performed 25 derotation tibial osteotomies as an isolated procedure or associated with a closed wedge osteotomy. We reviewed 15 patients (16–28 years old at surgery) with special reference to pain, aesthetic criteria and functional assessments, and we reported possible negative effects of derotation (recurvation and external tibial rotation). In all the patients we found an external rotation higher than standard range and moderate varus. All patients had remission of pain; this was complete in five and partial in six. Ten patients showed an increased tibial rotation and eight of those showed even recurvation without functional sequelae. At 2–12 years of follow-up, our results are satisfactory.

The average wait for a MRI Scan of the knee for an elective knee complaint is 12–18 months. This has a vast impact on family economy and quality of life considering the affected patients are young. We retrospectively reviewed 85 knee arthroscopies performed by a single surgeon during a one year period. We correlated the arthroscopy findings with the provisional diagnosis made in the clinic. There were 49 males and 36 females. The average wait for surgery was 4.6 months.The diagnosis was correct in 49 (60%), correct with additional findings in 18 (20%) and incorrect in 18 (20%). In a district general hospital setting where acces to MR Scan is difficult with a long waiting time, physical examination is reliable and arthroscopy can be performed after informed consent.

Aims. This systematic review and meta-analysis aimed to compare the influence of patellar resurfacing following cruciate-retaining (CR) and posterior-stabilized (PS) total knee arthroplasty (TKA) on the incidence of anterior knee pain, knee-specific patient-reported outcome measures, complication rates, and reoperation rates. Methods. A systematic review of MEDLINE, PubMed, and Google Scholar was performed to identify randomized controlled trials (RCTs) according to search criteria. Search terms used included: arthroplasty, replacement, knee (Mesh), TKA, prosthesis, patella, patellar resurfacing, and patellar retaining. RCTs that compared patellar resurfacing versus unresurfaced in primary TKA were included for further analysis. Studies were evaluated using the Scottish Intercollegiate Guidelines Network assessment tool for quality and minimization of bias. Data were synthesized and meta-analysis performed. Results. There were 4,135 TKAs (2,068 resurfaced and 2,027 unresurfaced) identified in 35 separate cohorts from 33 peer-reviewed studies. Anterior knee pain rates were significantly higher in unresurfaced knees overall (odds ratio (OR) 1.84; 95% confidence interval (CI) 1.20 to 2.83; p = 0.006) but more specifically associated with CR implants (OR 1.95; 95% CI 1.0 to 3.52; p = 0.030). There was a significantly better Knee Society function score (mean difference (MD) -1.98; 95% CI -1.1 to -2.84; p < 0.001) and Oxford Knee Score (MD -2.24; 95% CI -0.07 to -4.41; p = 0.040) for PS implants when patellar resurfacing was performed, but these differences did not exceed the minimal clinically important difference for these scores. There were no significant differences in complication rates or infection rates according to implant design. There was an overall significantly higher reoperation rate for unresurfaced TKA (OR 1.46 (95% CI 1.04 to 2.06); p = 0.030) but there was no difference between PS or CR TKA. Conclusion. Patellar resurfacing, when performed with CR implants, resulted in lower rates of anterior knee pain and, when used with a PS implant, yielded better knee-specific functional outcomes. Patellar resurfacing was associated with a lower risk of reoperation overall, but implant type did not influence this. Cite this article: Bone Joint J 2023;105-B(6):622–634

The August 2023 Knee Roundup. 360. looks at: Curettage and cementation of giant cell tumour of bone: is arthritis a given?; Anterior knee pain following total knee arthroplasty: does the patellar cement-bone interface affect postoperative anterior knee pain?; Nickel allergy and total knee arthroplasty; The use of artificial intelligence for the prediction of periprosthetic joint infection following aseptic revision total knee arthroplasty; Ambulatory unicompartmental knee arthroplasty: development of a patient selection tool using machine learning; Femoral asymmetry: a missing piece in knee alignment; Needle arthroscopy – a benefit to patients in the outpatient setting; Can lateral unicompartmental knees be done in a day-case setting?

The bone-patellar tendon-bone (BTB) autograft is associated with difficulty kneeling following anterior cruciate ligament (ACL) reconstruction, however it is unclear whether it results in a more painful or symptomatic knee when compared to the hamstring tendon autograft. This study aimed to identify the rate of significant knee pain and difficulty kneeling following primary ACL reconstruction and clarify whether graft type influences the risk of these complications. Primary ACL reconstructions prospectively recorded in the New Zealand ACL Registry between April 2014 and November 2019 were analyzed. The Knee Injury and Osteoarthritis Outcome Score (KOOS) was analyzed to identify patients who reported significant knee pain, defined as a KOOS Pain subscale score of ≤72 points, and kneeling difficulty, defined as a patient who reported “severe” or “extreme” difficulty when they kneel. The rate of knee pain and kneeling difficulty was compared between graft types via univariate Chi-square test and multivariate binary logistic regression with adjustment for patient demographics. 4492 primary ACL reconstructions were analyzed. At 2-year follow-up, 9.3% of patients reported significant knee pain (420/4492) and 12.0% reported difficulty with kneeling (537/4492). Patients with a BTB autograft reported a higher rate of kneeling difficulty compared to patients with a hamstring tendon autograft (21.3% versus 9.4%, adjusted odds ratio = 3.12, p<0.001). There was no difference between graft types in the rate of significant knee pain (9.9% versus 9.2%, p = 0.49) or when comparing absolute values of the KOOS Pain (mean score for BTB = 88.7 versus 89.0, p = 0.37) and KOOS Symptoms subscales (mean score for BTB = 82.5 versus 82.1, p = 0.49). The BTB autograft is a risk factor for post-operative kneeling difficulty, but it does not result in a more painful or symptomatic knee when compared to the hamstring tendon autograft

Abstract. Objective. A common orthopaedic pain found in a wide spectrum of individuals, from young and active to the elderly is anterior knee pain (AKP). It is a multifactorial disorder which is thought to occur through muscular imbalance, overuse, trauma, and structural malalignment. Over time, this can result in cartilage damage and subsequent chondral lesions. Whilst the current gold standard for chondral lesion detection is MRI, it is not a highly sensitive tool, with around 20% of lesions thought to be mis-diagnosed by MRI. Single-photon emission computerised tomography with conventional computer tomography (SPECT/CT) is an emerging technology, which may hold clinical value for the detection of chondral lesions. SPECT/CT may provide valuable diagnostic information for AKP patients who demonstrate absence of structural change on other imaging modalities. This review systematically assessed the value of SPECT/CT as an imaging modality for knee pain, and its ability to diagnose chondral lesions for patients who present with knee pain. Methods. Using PRISMA guidelines, a systematic search was carried out in PubMed, Science Direct, and Web of Knowledge, CINAHL, AMED, Ovid Emcare and Embase. Inclusion criteria consisted of any English language article focusing on the diagnostic value of SPECT/CT for knee chondral lesions and knee pain. Furthermore, animal or cadaver studies, comparator technique other than SPECT/CT or patients with a pathology other than knee chondral lesions were excluded from the study. Relevant articles underwent QUADAS-2 bias assessment. Results. 11,982 manuscripts were identified, and the titles were screened for relevance. Seven studies were selected as being appropriate and were subjected to QUADAS-2 assessment. All 7 articles scored low for bias. Two papers deemed that the ICRS score of chondral lesions at intraoperative assessment correlated with SPECT/CT tracer uptake. Two studies concluded that MRI significantly correlated with SPECT/CT tracer uptake, with some instances whereby SPECT/CT identified more chondral lesions than MRI. Two papers compared bone scintigraphy (BS) to SPECT/CT and concluded that SPECT/CT was not only able to identify more chondral lesions than BS, but also localise and characterise the lesions. Conclusion. Evidence implies that SPECT/CT may be a useful imaging modality for the detection and localisation of cartilage lesions, particularly in discrepant cases whereby there is an absence of lesions on other imaging modalities, or a lack of correspondence with patients’ symptoms. More studies would be of value to confirm the conclusions of this review. Declaration of Interest. (b) declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research reported:I declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research project

Knee pain is common, representing a significant socioeconomic burden. Caused by a variety of pathologies, its evaluation in primary-care is challenging. Subsequently, an over-reliance on magnetic resonance imaging (MRI) exists. Prior to orthopaedic surgeon referral, many patients receive no, or incorrect, imaging. Electronic-triage (e-triage) tools represent an innovative solution to address this problem. The primary aim of this study was to ascertain whether an e-triage tool is capable of outperforming existing clinical pathways to determine the correct pre-hospital imaging based on knee pain diagnosis. Patients ≥18 years with a new presentation of knee pain were retrospectively identified. The timing and appropriateness of imaging was assessed. A symptom-based e-triage tool was developed, using the Amazon LEXbotplatform, and piloted to predict five common knee pathologies and suggest appropriate imaging. 1462 patients were identified. 17% of arthroplasty patients received an ‘unnecessary MRI’, whilst 28% of arthroscopy patients did not have a ‘necessary MRI’, thus requiring a follow-up appointment, with a mean delay of three months (SD 2.6, range 0.2-20.2). Using NHS tariffs, a wasted cost through unnecessary/necessary MRIs and subsequent follow-up appointments was estimated at £45,816. The e-triage pilot was trialled with 41 patients (mean age:58.4 years, 58.5% female). Preliminary diagnoses were available for 34 patients. Using the highest proportion of reported symptoms in the corresponding group, the e-triage tool correctly identified three of the four knee pathologies. The e-triage tool did not correctly identify anterior cruciate ligament injuries (n=3). 79.2% of participants would use the tool again. A significant number of knee pathology patients received incorrect imaging prior to their initial hospital appointment, incurring delays and unnecessary costs. A symptom-based e-triage tool was developed, with promising pilot data and user feedback. With refinement, this tool has the potential to improve wait-times and referral quality, whilst reducing costs

Abstract. INTRODUCTION. Geniculate nerve blocks (GNB) and ablation (GNA) are increasing in popularity as strategies for the management of knee pain in patients unsuitable for surgical intervention. Typically these simple blocks have been performed by specialists in pain medicine. We present the results of a GNB clinic run by a surgical care practitioner (SCP). METHODOLOGY. An SCP clinic was created where ultrasound-guided GNBs comprising local anaesthetic and steroid were administered. Patients considered unsuitable for surgery were referred with knee pain by orthopaedic knee surgeons and specialist physiotherapists. A VAS pain score and an Oxford Knee Score (OKS) were completed prior to and immediately following blockade. Serial VAS diaries were completed. Further OKS were requested at 6 weeks and 6 months. Patients could request GNA at any point during follow-up and their follow-up ceased at this stage. RESULTS. 50 patients were identified between December 2020 and 2021. Patients are followed up until 6 months post-block or until referral for GNA. Pre-blockade mean OKS was 13.4, mean VAS 8.6, post procedure mean VAS 2.7. Six-week mean OKS was 20.9 in those not referred for ablation, mean improvement of 7.3. Of the cohort of 50, 25 have progressed to ablation. CONCLUSION. GNB is a simple procedure which can provide both lasting symptomatic relief and prognostic information in the treatment of patients with knee pain not amenable to surgical intervention, a growing subset of patients. This SCP-led clinic increases capacity for the provision of GNBs, helping to identify patients suitable for GNA

Individuals with multi-compartment knee osteoarthritis (KOA) frequently experience challenges in activities of daily living (ADL) such as stair ambulation. The Levitation “Tri-Compartment Offloader” (TCO) knee brace was designed to reduce pain in individuals with multicompartment KOA. This brace uses novel spring technology to reduce tibiofemoral and patellofemoral forces via reduced quadriceps forces. Information on brace utility during stair ambulation is limited. This study evaluated the effect of the TCO during stair descent in patients with multicompartment KOA by assessing knee flexion moments (KFM), quadriceps activity and pain. Nine participants (6 male, age 61.4±8.1 yrs; BMI 30.4±4.0 kg/m2) were tested following informed consent. Participants had medial tibiofemoral and patellofemoral OA (Kellgren-Lawrence grades two to four) diagnosed by an orthopaedic surgeon. Joint kinetics and muscle activity were evaluated during stair descent to compare three bracing conditions: 1) without brace (OFF); 2) brace in low power (LOW); and 3) brace in high power (HIGH). The brace spring engages from 60° to 120° and 15° to 120° knee flexion in LOW and HIGH, respectively. Individual brace size and fit were adjusted by a trained researcher. Participants performed three trials of step-over-step stair descent for each bracing condition. Three-dimensional kinematics were acquired using an 8-camera motion capture system. Forty-one spherical reflective markers were attached to the skin (on each leg and pelvis segment) and 8 markers on the brace. Ground reaction forces and surface EMG from the vastus medialis (VM) and vastus lateralis (VL) were collected for the braced leg. Participants rated knee pain intensity performing the task following each bracing condition on a 10cm Visual Analog Scale ranging from “no pain” (0) to “worst imaginable pain” (100). Resultant brace and knee flexion angles and KFM were analysed during stair contact for the braced leg. The brace moment was determined using brace torque-angle curves and was subtracted from the calculated KFM. Resultant moments were normalized to bodyweight and height. Peak KFMs were calculated for the loading response (Peak1) and push-off (Peak2) phases of support. EMG signals were normalized and analysed during stair contact using wavelet analysis. Signal intensities were summed across wavelets and time to determine muscle power. Results were averaged across all 3 trials for each participant. Paired T-tests were used to determine differences between bracing conditions with a Bonferroni adjustment for multiple comparisons (α=0.025). Peak KFM was significantly lower compared to OFF with the brace worn in HIGH during the push-off phase (p Table 1: Average peak knee flexion moments, quadriceps muscle power and knee pain during stair descent in 3 brace conditions (n=9). Quadriceps activity, knee flexion moments and pain were significantly reduced with TCO brace wear during stair descent in KOA patients. These findings suggest that the TCO assists the quadriceps to reduce KFM and knee pain during stair descent. This is the first biomechanical evidence to support use of the TCO to reduce pain during an ADL that produces especially high knee forces and flexion moments. For any figures or tables, please contact the authors directly

The August 2024 Trauma Roundup. 360. looks at: Does topical vancomycin prevent fracture-related infections in closed fractures undergoing open reduction and internal fixation? A randomized controlled trial; Is postoperative splinting advantageous after upper limb fracture surgery?; Does suprapatellar nailing resolve knee pain?; Locking versus non-locking plate fixation in comminuted talar neck fractures: a biomechanical study using cadaveric specimens; Revolutionizing recovery metrics: PROMIS versus SMFA in orthopaedic trauma care; Dorsal hook plating of patella fractures: reliable fixation and satisfactory outcomes; The impact of obesity on subtrochanteric femur fracture outcomes; Low-dose NSAIDs (ketorolac) and cytokine modulation in orthopaedic polytrauma: a detailed analysis

Abstract. Aims. The aim of this study was to evaluate the indications for patients presenting with knee pain undergoing magnetic resonance imaging of the knee prior to referral to the orthopaedic department and to ascertain whether plain radiograph imagining would be more beneficial prior to an MRI scan. Method. A retrospective review of all referrals received by the hospital over a 6-month period was performed. Patients with knee pain that underwent an MRI scan were classified into two age groups, under 50 years and over 50 years old. Patients having undergone Magnetic resonance imaging (MRI) prior to referral were identified, and findings of the scan were recorded. These patients were reviewed further to see if a plain radiograph had been completed prior to or after the MRI. Results. A total of 414 patients were referred. In the over 50's 228 MRI scans were performed. Of these 103/228 patients the predominate finding was meniscal tears and 72/228 had a finding of osteoarthritis. A plain radiograph of the knee was completed 99/228 cases, 28/99 before the MRI. In the under 50's 186 scans were performed and of these 85/186 the predominate finding was meniscal tears. A plain radiograph of the knee was completed in only eighty-three (83/186) cases, (69/83) before the MRI. Conclusion. In over 50s, 57% of patients (129 of 228) did not have a knee X-ray before having an MRI. For a single hospitals referral over 6 months these unnecessary MRI of knee cost the National Health Services £7,500

Pelvic bone defect in patients with severe congenital dysplasia of the hip (CDH) lead to abnormalities in lumbar spine and lower limb alignment that can determine total hip arthroplasty (THA) patients' outcome. These variables may be different in uni- or bilateral CDH. We compared the clinical outcome and the spinopelvic and lower limb radiological changes over time in patients undergoing THA due to uni- or bilateral CHD at a minimum follow-up of five years. Sixty-four patients (77 hips) undergoing THA due to severe CDH between 2006 and 2015 were analyzed: Group 1 consisted of 51 patients with unilateral CDH, and group 2, 113 patients (26 hips) with bilateral CDH. There were 32 females in group 1 and 18 in group 2 (p=0.6). The mean age was 41.6 years in group 1 and 53.6 in group 2 (p<0.001). We compared the hip, spine and knee clinical outcomes. The radiological analysis included the postoperative hip reconstruction, and the evolution of the coronal and sagittal spinopelvic parameters assessing the pelvic obliquity (PO) and the sacro-femoro-pubic (SFP) angles, and the knee mechanical axis evaluating the tibio-femoral angle (TFA). At latest follow-up, the mean Harris Hip Score was 88.6 in group 1 and 90.7 in group 2 (p=0.025). Postoperative leg length discrepancy of more than 5 mm was more frequent in group 1 (p=0.028). Postoperative lumbar back pain was reported in 23.4% of the cases and knee pain in 20.8%, however, there were no differences between groups. One supracondylar femoral osteotomy and one total knee arthroplasty were required. The radiological reconstruction of the hip was similar in both groups. The PO angle improved more in group 1 (p=0.01) from the preoperative to 6-weeks postoperative and was constant at 5 years. The SFP angle improved in both groups but there were no differences between groups (p=0.5). 30 patients in group 1 showed a TFA less than 10º and 17 in group 2 (p=0.7). Although the clinical outcome was better in terms of hip function in patients with bilateral CDH than those with unilateral CDH, the improvement in low back and knee pain was similar. Patients with unilateral dysplasia showed a better correction of the PO after THA. All spinopelvic and knee alignment parameters were corrected and maintained over time in most cases five years after THA

Aims. The aim was to assess whether robotic-assisted total knee arthroplasty (rTKA) had greater knee-specific outcomes, improved fulfilment of expectations, health-related quality of life (HRQoL), and patient satisfaction when compared with manual TKA (mTKA). Methods. A randomized controlled trial was undertaken (May 2019 to December 2021), and patients were allocated to either mTKA or rTKA. A total of 100 patients were randomized, 50 to each group, of whom 43 rTKA and 38 mTKA patients were available for review at 12 months following surgery. There were no statistically significant preoperative differences between the groups. The minimal clinically important difference in the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) pain score was defined as 7.5 points. Results. There were no clinically or statistically significant differences between the knee-specific measures (WOMAC, Oxford Knee Score (OKS), Forgotten Joint Score (FJS)) or HRQoL measures (EuroQol five-dimension questionnaire (EQ-5D) and EuroQol visual analogue scale (EQ-VAS)) at 12 months between the groups. However, the rTKA group had significantly (p = 0.029) greater improvements in the WOMAC pain component (mean difference 9.7, 95% confidence interval (CI) 1.0 to 18.4) over the postoperative period (two, six, and 12 months), which was clinically meaningful. This was not observed for function (p = 0.248) or total (p = 0.147) WOMAC scores. The rTKA group was significantly (p = 0.039) more likely to have expectation of ‘Relief of daytime pain in the joint’ when compared with the mTKA group. There were no other significant differences in expectations met between the groups. There was no significant difference in patient satisfaction with their knee (p = 0.464), return to work (p = 0.464), activities (p = 0.293), or pain (p = 0.701). Conclusion. Patients undergoing rTKA had a clinically meaningful greater improvement in their knee pain over the first 12 months, and were more likely to have fulfilment of their expectation of daytime pain relief compared with patients undergoing mTKA. However, rTKA was not associated with a clinically significant greater knee-specific function or HRQoL, according to current definitions. Cite this article: Bone Joint J 2024;106-B(5):450–459

Introduction. Overwhelming evidence has established obesity as a risk factor for osteoarthritis (OA) of the knee. Randomized clinical trials such as the Look AHEAD study have shown long term successful intentional weight loss with an intensive lifestyle intervention (ILI) in overweight and obese type 2 diabetics. Weight loss can also decrease knee pain in persons who have OA, but it is unknown if intentional weight loss can reduce the risk of TKR. To answer this question, data from the Look AHEAD study were examined to determine if intentional weight loss could reduce the risk of TKR. Methods. Look AHEAD is a multicenter, randomized trial which began in August 2001 and follow-up continued for a median of 11.3 years at 16 academic centers. 5145 persons aged 45–76 with diabetes were randomized to either an ILI with reduced calorie consumption and increased physical activity designed or to diabetes support and education intervention (DSE). TKR events were ascertained every 6 months. Retrospective data of reported knee pain was assessed using the WOMAC knee pain questionnaire. Participants with partial TKR or revisions were excluded. Cox proportional hazard models were used to relate baseline BMI category (obese, Class I, Class II, or Class III obesity), baseline knee pain, and treatment group with TKR. Weight change category (lost<=5%, stable, gained>=2%) from baseline to year 1 follow-up by treatment assignment was also examined as a predictor of TKR after excluding TKR occurring prior to year 1. Results. Out of the randomized participants, 2171 reported knee pain (43%) at the baseline visit (p=0.81). WOMAC knee pain score did not differ by random assignment (ILI:3.6±2.9, DSE:3.9±3.0, p=0.08). During follow up there were 631 TKRs reported by participants. TKR was more common in heavier (p<0.001), and older (p<0.001) participants and did not differ by randomization. Heterogeneity of treatment effect was observed with baseline knee pain (interaction p = 0.02), therefore analyses were stratified by presence or absence of knee pain at baseline. In persons without knee pain at baseline, there was a 29% reduced rate of TKR in the ILI group compared to the DSE group (HR[95%CI] 0.71[0.52,0.96]; Figure 1A). Whereas in persons with knee pain at baseline, there was a trend for the ILI to have an increased rate of TKR compared to DSE (1.11[0.92, 1.33]; Figure 1B). In both sets of analyses, obese participants had significantly higher hazard of TKR than overweight participants (No pain: Class I 1.78[1.04,3.05], Class II 2.27 [1.31,3.94], Class III 2.94[1.67,5.18]; With pain: Class I 1.70[1.12,2.59], Class II 2.42 [1.60,3.65], Class III 2.80[1.85,4.23]). When TKR incidence was examined by weight change at year 1 there was no difference in weight change category between randomization groups in persons with knee pain (interaction p=0.20) or without baseline knee pain (interaction p=0.87) (Figure 1C and D) or for the overall effect of year 1 weight loss category in either stratum (with knee pain p=0.26, without knee pain p=0.48). However, in persons without knee pain at baseline, ILI had a marginal reduction in hazard of TKR compared to DSE (0.71[0.49, 1.05]) but not in the group with baseline knee pain. Conclusions. In persons with no knee pain at baseline and who were overweight or had Class I or II obesity, ILI seemed to reduce the risk of TKR compared to DSE. In contrast, persons with knee pain who gained weight at 1 year and were randomized to ILI had the highest risk of TKR. This suggests that weight loss to prevent TKR may be more effective prior to the development of significant knee pain. After the onset of knee pain however, low impact or non-weight bearing activity should be considered to avoid worsening knee symptoms. For any figures or tables, please contact authors directly

Aims. The aims of this study were to investigate the ability to kneel after total knee arthroplasty (TKA) without patellar resurfacing, and its effect on patient-reported outcome measures (PROMs). Secondary aims included identifying which kneeling positions were most important to patients, and the influence of radiological parameters on the ability to kneel before and after TKA. Methods. This prospective longitudinal study involved 209 patients who underwent single radius cruciate-retaining TKA without patellar resurfacing. Preoperative EuroQol five-dimension questionnaire (EQ-5D), Oxford Knee Score (OKS), and the ability to achieve four kneeling positions were assessed including a single leg kneel, a double leg kneel, a high-flexion kneel, and a praying position. The severity of radiological osteoarthritis (OA) was graded and the pattern of OA was recorded intraoperatively. The flexion of the femoral component, posterior condylar offset, and anterior femoral offset were measured radiologically. At two to four years postoperatively, 151 patients with a mean age of 70.0 years (SD 9.44) were included. Their mean BMI was 30.4 kg/m. 2. (SD 5.36) and 60 were male (40%). They completed EQ-5D, OKS, and Kujala scores, assessments of the ability to kneel, and a visual analogue scale for anterior knee pain and satisfaction. Results. The ability to kneel in the four positions improved in between 29 (19%) and 53 patients (35%) after TKA, but declined in between 35 (23%) and 46 patients (30%). Single-leg kneeling was most important to patients. After TKA, 62 patients (41%) were unable to achieve a single-leg kneel, 76 (50%) were unable to achieve a double-leg kneel, 102 (68%) were unable to achieve a high-flexion kneel and 61 (40%) were unable to achieve a praying position. Posterolateral cartilage loss significantly affected preoperative deep flexion kneeling (p = 0.019). A postoperative inability to kneel was significantly associated with worse OKS, Kujala scores, and satisfaction (p < 0.05). Multivariable regression analysis identified significant independent associations with the ability to kneel after TKA (p < 0.05): better preoperative EQ-5D and flexion of the femoral component for single-leg kneeling; the ability to achieve it preoperatively and flexion of the femoral component for double-leg kneeling; male sex for high-flexion kneeling; and the ability to achieve it preoperatively, anterior femoral offset, and patellar cartilage loss for the praying position. Conclusion. The ability to kneel was important to patients and significantly influenced knee-specific PROMs, but was poorly restored by TKA with equal chances of improvement or decline. Cite this article: Bone Joint J 2021;103-B(9):1514–1525

Discoid meniscus (DM) is a congenital variant of the knee joint that involves morphological and structural deformation, with potential meniscal instability. The prevalence of the Discoid Lateral Meniscus (DLM) is higher among the Asians than among other races, and both knees are often involved. Meniscal pathology is widely prevalent in the adult population, secondary to acute trauma and chronic degeneration. The true prevalence in children remains unknown, as pathologies such as discoid menisci often go undiagnosed, or are only found incidentally. A torn or unstable discoid meniscus can present with symptoms of knee pain, a snapping or clicking sensation and/or a decrease in functional activity, although it is not known if a specific presentation is indicative of a torn DM. While simple radiographs may provide indirect signs of DLM, magnetic resonance imaging (MRI) and arthroscopy is essential for diagnosis and treatment planning. Asymptomatic patients require close follow-up without surgical treatment, while patients with symptoms often require surgery. Partial meniscectomy is currently considered the treatment of choice for DLM. For children are more likely to achieve better results after partial meniscectomy

Total Knee Arthroplasty (TKA) is a successful treatment for end stage osteoarthritis of the knee joint. However, post-operative pain can lead to patient dissatisfaction and poorer outcomes. Cooled radiofrequency nerve ablation (CRNA) has reportedly been effective at treating pain osteoarthritic knee pain by targeting the periarticular nerves of the knee. We undertook a prospective, controlled pilot study to determine if CRNA provides effective post-operative analgesia when utilised intra-operatively during total knee arthroplasty. Participants were recruited from January 2019 to February 2020. Those meeting inclusion criteria underwent TKA with intraoperative CRNA to 6 target sites prior to the cementing of implants. The primary outcomes were pain scores and opiate usage in the first 4 days post-operatively, then weekly up to 6 weeks. A total of 62 patients were screened and allocated sequentially; 18 were recruited to the control group and 12 recruited to the study group. The two groups did not have any significant difference in demographics. There were no clinically significant differences between the two groups in terms of pain scores nor opiate usage. There were complications as a result of the intervention. This study demonstrated no benefit of using intraoperative CRNA for improving post-operative pain scores or reducing opiate use after TKA

Patellofemoral instability (PFI) is a common cause of knee pain and disability in the paediatric population. Patella alta, lateralised tibial tubercle, medial patellofemoral ligament (MPFL) deficiency, genu valgum and trochlear dysplasia are well known risk factors. A prospective database was created including patients referred through our physiotherapy pathway following first-time patella dislocation. Patella alta and lateralisation of the tibial tuberosity was treated with a Fulkerson-type tibial tubercle osteotomy(TTO). Medial patellofemoral ligament was reconstructed using quads tendon autograft pull-down technique. A modified Sheffield protocol was used postoperatively allowing weightbearing in a hinged knee brace. Forty patients were identified with 8 patients having bilateral presentations. Male to female ratio was 12:28 with an age range of 4–17 years. Eight patients had congenital PFI, five patients acquired PFI through traumatic patella dislocation and twenty-seven patients developed PFI from recurrent dislocations. Structural abnormalities were found in 38(95%) of patients. Patella alta (Caton-Deschamps index >1.2) was identified in 19(47%) patients, genu valgum in 12(30%) patients, increased tibial tubercle-trochlear groove distance(TT-TG>20mm) was present in 9(22.5%) patients and persistent femoral anteversion(> 20 deg) in 7(17%) patients. Eight patients were treated with TTO and MPFL reconstruction, three patients with MPFL reconstruction alone and five patients had guided growth for genu valgum correction. Ten patients are awaiting surgery. No postoperative patients had recurrence of PFI at their latest follow up. PFI is a common problem in the adolescent paediatric population with identifiable structural abnormalities. Correcting structural pathology with surgery leads to predictable and safe outcomes