Aims. Knowledge on total knee arthroplasties (TKAs) in patients with a history of poliomyelitis is limited. This study compared implant survivorship and clinical outcomes among affected and unaffected limbs in patients with sequelae of poliomyelitis undergoing TKAs. Methods. A retrospective review of our total joint registry identified 94 patients with post-polio syndrome undergoing 116 primary TKAs between January 2000 and December 2019. The mean age was 70 years (33 to 86) with 56% males (n = 65) and a mean BMI of 31 kg/m. 2. (18 to 49). Rotating hinge TKAs were used in 14 of 63 affected limbs (22%), but not in any of the 53 unaffected limbs. Kaplan-Meier survivorship analyses were completed. The mean follow-up was eight years (2 to 19). Results. The ten-year survivorship free from revision was 91% (95% confidence interval (CI) 81 to 100) in affected and 84% (95% CI 68 to 100) in unaffected limbs. There were six revisions in affected limbs: three for periprosthetic femoral fractures and one each for periprosthetic joint infection (PJI), patellar clunk syndrome, and instability. Unaffected limbs were revised in four cases: two for instability and one each for PJI and tibial component loosening. The ten-year survivorship free from any reoperation was 86% (95% CI 75 to 97) and 80% (95% CI 64 to 99) in affected and unaffected limbs, respectively. There were three additional reoperations among affected and two in unaffected limbs. There were 12 nonoperative complications, including four periprosthetic fractures. Arthrofibrosis occurred in five affected (8%) and two unaffected limbs (4%). Postoperative range of motion decreased with 31% achieving less than 90° knee flexion by five years. Conclusion. TKAs in post-polio patients are complex cases associated with instability, and one in four require constraint on the affected side. Periprosthetic fracture was the main mode of failure. Arthrofibrosis rates were high and twice as frequent in affected limbs. Cite this article: Bone Joint J 2023;105-B(6):635–640

Aim. Nail patella syndrome (NPS) is a skeletal dysplasia with patellofemoral dysfunction as a key symptom. We present the first in-depth radiological evaluation of the knee in a large series of NPS patients and describe the typical malformations. Patients and Methods. Conventional radiological examination of 95 skeletally mature patients with NPS was performed. Patellar morphology was classified according to the Wiberg classification as modified by Baumgartl and Ficat criteria, and trochlear shape was classified according to the Dejour classification. Results. Patellar aplasia was present in 4/90 (4%), and patellar hypoplasia in 77/90 (86%) of patients. The prevailing patellar shapes were type III, type IV and Hunter’s cap. No patellar shape genotype-phenotype association could be found. The malformations of the distal femur comprised shortening of the lateral femoral condyle in 46 out of 84 patients (55%), with a prominent anterior surface of the lateral femoral condyle in 47 out of 84 patients (56%) and a flat anterior surface of the medial femoral condyle in 78 out of 85 patients (92%). The trochlea was type A1 according to the Dejour classification in 79 out of 85 patients (93%). . Conclusion. An easily recognisable characteristic quartet of malformations consisting of patellar aplasiaor hypoplasia and the malformations of the distal femur was found in 22 out of 81 patients (27%), with the majority displaying at least three malformations. Take home message: The distinct malformations of the knee in nail patella syndrome are easily recognisable on conventional radiographs and lead to the correct interpretation of the aberrant morphology which is essential in the treatment of these patellofemoral disorders. Cite this article: Bone Joint J 2016;98-B:483–9

The patellar clunk syndrome describes painful catching, grinding or jumping of the patella when the knee moves from a flexed to an extended position after total knee replacement (TKR). The posterior stabilised TKR had been noted to have a higher incidence of this problem. Mobile-bearing posteriorly stabilised TKRs have been introduced to improve patellar tracking and related problems by a mechanism of self-alignment. We evaluated the patellar clunk syndrome in 113 knees in 93 patients with such a TKR at a mean follow-up of 2.3 years (2.0 to 3.2). The syndrome was identified in 15 knees (13.3%). Logistic regression analysis showed that the absolute value of the post-operative angle of patellar tilt was significantly associated with the occurrence of patellar clunk (p = 0.025). Patellar tracking should be carefully checked during surgery

We present a series of four patients with what we have termed the snapping pes syndrome. This is a painful clicking and catching experienced at the posteromedial corner of the knee when moving from flexion to extension. Clinical examination and real time ultrasound are the most useful diagnostic tools. If medical treatment is unsuccessful surgical excision of both the semitendinous and gracilis tendons is indicated for relief of persistent symptoms

Compartment syndrome is a rare complication of total knee arthroplasty that requires early recognition and prompt decompression in order to prevent long-term disability. We have found only one previous case report in the literature. We present a series of seven cases from four hospitals and five surgeons. Six of the cases resulted in the loss of at least one compartment, and one resulted in amputation. Four of the cases resulted in legal action. We suggest that important risk factors contributing to the development of this condition include complex surgery, soft-tissue compromise, previous surgery, and possibly vascular disease. Delay in the diagnosis and hence delay in decompression was common in our series, and in five cases appeared to be related to the use of a postoperative epidural infusion for pain relief. The presence of associated neurological compromise may have also been a significant factor in the delay to diagnosis in two cases

Aims

The aim of this study was to establish consensus statements on medial patellofemoral ligament (MPFL) reconstruction, anteromedialization tibial tubercle osteotomy, trochleoplasty, and rehabilitation and return to sporting activity in patients with patellar instability, using the modified Delphi process.

Aims

The antidiabetic agent metformin inhibits fibrosis in various organs. This study aims to elucidate the effects of hyperglycaemia and metformin on knee joint capsule fibrosis in mice.

Aims

The use of high tibial osteotomy (HTO) to delay total knee arthroplasty (TKA) in young patients with osteoarthritis (OA) and constitutional deformity remains debated. The aim of this study was to compare the long-term outcomes of TKA after HTO compared to TKA without HTO, using the time from the index OA surgery as reference (HTO for the study group, TKA for the control group).

Aims

Despite new technologies for total knee arthroplasty (TKA), approximately 20% of patients are dissatisfied. A major reason for dissatisfaction and revision surgery after TKA is persistent pain. The radiological grade of osteoarthritis (OA) preoperatively has been investigated as a predictor of the outcome after TKA, with conflicting results. The aim of this study was to determine if there is a difference in the intensity of pain 12 months after TKA in relation to the preoperative radiological grade of OA alone, and the combination of the intensity of preoperative pain and radiological grade of OA.

Aims

To map literature on prognostic factors related to outcomes of revision total knee arthroplasty (rTKA), to identify extensively studied factors and to guide future research into what domains need further exploration.

Aims. The aim of this consensus was to develop a definition of post-operative fibrosis of the knee. Patients and Methods. An international panel of experts took part in a formal consensus process composed of a discussion phase and three Delphi rounds. Results. Post-operative fibrosis of the knee was defined as a limited range of movement (ROM) in flexion and/or extension, that is not attributable to an osseous or prosthetic block to movement from malaligned, malpositioned or incorrectly sized components, metal hardware, ligament reconstruction, infection (septic arthritis), pain, chronic regional pain syndrome (CRPS) or other specific causes, but due to soft-tissue fibrosis that was not present pre-operatively. Limitation of movement was graded as mild, moderate or severe according to the range of flexion (90° to 100°, 70° to 89°, < 70°) or extension deficit (5° to 10°, 11° to 20°, > 20°). Recommended investigations to support the diagnosis and a strategy for its management were also agreed. Conclusion. The development of standardised, accepted criteria for the diagnosis, classification and grading of the severity of post-operative fibrosis of the knee will facilitate the identification of patients for inclusion in clinical trials, the development of clinical guidelines, and eventually help to inform the management of this difficult condition. Cite this article: Bone Joint J 2016;98-B:1479–88

Aims

This study aimed to investigate the relationship between changes in patellar height and clinical outcomes at a mean follow-up of 7.7 years (5 to 10) after fixed-bearing posterior-stabilized total knee arthroplasty (PS-TKA).

Aims

Intra-articular administration of antibiotics during primary total knee arthroplasty (TKA) may represent a safe, cost-effective strategy to reduce the risk of acute periprosthetic joint infection (PJI). Vancomycin with an aminoglycoside provides antimicrobial cover for most organisms isolated from acute PJI after TKA. However, the intra-articular doses required to achieve sustained therapeutic intra-articular levels while remaining below toxic serum levels is unknown. The purpose of this study is to determine the intra-articular and serum levels of vancomycin and tobramycin over the first 24 hours postoperatively after intra-articular administration in primary cementless TKA.

Aims

Infection complicating primary total knee arthroplasty (TKA) is a common reason for revision surgery, hospital readmission, patient morbidity, and mortality. Increasing incidence of methicillin-resistant Staphylococcus aureus (MRSA) is a particular concern. The use of vancomycin as prophylactic agent alone or in combination with cephalosporin has not demonstrated lower periprosthetic joint infection (PJI) rates, partly due to timing and dosing of intravenous (IV) vancomycin administration, which have proven important factors in effectiveness. This is a retrospective review of a consecutive series of primary TKAs examining incidence of PJI, adverse reactions, and complications using IV versus intraosseous (IO) vancomycin at 30-day, 90-day, and one-year follow-up.

Aims

The primary aim of this study was to assess whether non-fatal postoperative venous thromboembolism (VTE) within six months of surgery influences the knee-specific functional outcome (Oxford Knee Score (OKS)) one year after total knee arthroplasty (TKA). Secondary aims were to assess whether non-fatal postoperative VTE influences generic health and patient satisfaction at this time.

Aims

Tourniquets have potential adverse effects including postoperative thigh pain, likely caused by their ischaemic and possible compressive effects. The aims of this preliminary study were to determine if it is possible to directly measure intramuscular pH in human subjects over time, and to measure the intramuscular pH changes resulting from tourniquet ischaemia in patients undergoing knee arthroscopy.

Aims

MRI has been suggested as an objective method of assessing anterior crucate ligament (ACL) graft “ligamentization” after reconstruction. It has been proposed that the MRI appearances could be used as an indicator of graft maturity and used as part of a return-to-sport assessment. The aim of this study was to evaluate the correlation between MRI graft signal and postoperative functional scores, anterior knee laxity, and patient age at operation.

Aims

The optimal management of an infrapopliteal deep venous thrombosis (IDVT) following total knee arthroplasty (TKA) remains unknown. The risk of DVT propagation and symptom progression must be balanced against potential haemorrhagic complications associated with administration of anticoagulation therapy. The current study reports on a cohort of patients diagnosed with IDVT following TKA who were treated with aspirin, followed closely for development of symptoms, and scanned with ultrasound to determine resolution of IDVT.

Aims

Debridement, antibiotics, and implant retention (DAIR) remains one option for the treatment of acute periprosthetic joint infection (PJI) despite imperfect success rates. Intraosseous (IO) administration of vancomycin results in significantly increased local bone and tissue concentrations compared to systemic antibiotics alone. The purpose of this study was to evaluate if the addition of a single dose of IO regional antibiotics to our protocol at the time of DAIR would improve outcomes.

Aims

The primary aim of this study was to compare the postoperative systemic inflammatory response in conventional jig-based total knee arthroplasty (conventional TKA) versus robotic-arm assisted total knee arthroplasty (robotic TKA). Secondary aims were to compare the macroscopic soft tissue injury, femoral and tibial bone trauma, localized thermal response, and the accuracy of component positioning between the two treatment groups.

Aims

We report the natural course of Baker’s cysts following total knee arthroplasty (TKA) at short- and mid-term follow-up.

Aims

To date, no study has demonstrated an improvement in postoperative outcomes following elective joint arthroplasty with a focus on nutritional intervention for patients with preoperative hypoalbuminaemia. In this prospective study, we evaluated differences in the hospital length of stay (LOS), rate of re-admission, and total patient charges for a malnourished patient study population who received a specific nutrition protocol before surgery.

Aims

The aim of this study was to determine the general postoperative opioid consumption and rate of appropriate disposal of excess opioid prescriptions in patients undergoing primary unilateral total knee arthroplasty (TKA).

Aims

Adductor canal block (ACB) has emerged as an alternative to femoral nerve block (FNB) for analgesia after total knee arthroplasty (TKA). The optimal duration of maintenance of the ACB is still questionable. The purpose of this study was to compare the analgesic benefits and physiotherapy (PT) outcomes of single-shot ACB to two different regimens of infusion of the continuous ACB, 24-hour and 48-hour infusion.

Aims

There is little information regarding the risk of a patient developing prosthetic joint infection (PJI) after primary total knee arthroplasty (TKA) when the patient has previously experienced PJI of a TKA or total hip arthroplasty (THA) in another joint. The goal of this study was to compare the risk of PJI of primary TKA in this patient population against matched controls.

Aims

The best marker for assessing glycaemic control prior to total knee arthroplasty (TKA) remains unknown. The purpose of this study was to assess the utility of fructosamine compared with glycated haemoglobin (HbA1c) in predicting early complications following TKA, and to determine the threshold above which the risk of complications increased markedly.

Aims

With an ageing population of patients who are infected with hepatitis C virus (HCV), the demand for total knee arthroplasty (TKA) in this high-risk group continues to grow. It has previously been shown that HCV infection predisposes to poor outcomes following TKA. However, there is little information about the outcome of TKA in patients with HCV who have been treated successfully. The purpose of this study was to compare the outcomes of TKA in untreated HCV patients and those with HCV who have been successfully treated and have a serologically confirmed remission.

Aims

The Bereiter trochleoplasty has been used in our unit for 12 years to manage recurrent patellar instability in patients with severe trochlea dysplasia. The aim of this study was to document the outcome of a large consecutive cohort of patients who have undergone this operation.

Objectives

The length of the tourniquet time during total knee arthroplasty (TKA) is related to the incidence of post-operative deep vein thrombosis (DVT). Our aim in this study was to investigate the effect of the early release of the tourniquet on the incidence of DVT in patients undergoing TKA.

Patellar instability most frequently presents during adolescence. Congenital and infantile dislocation of the patella is a distinct entity from adolescent instability and measurable abnormalities may be present at birth. In the normal patellofemoral joint an increase in quadriceps angle and patellar height are matched by an increase in trochlear depth as the joint matures. Adolescent instability may herald a lifelong condition leading to chronic disability and arthritis.

Restoring normal anatomy by trochleoplasty, tibial tubercle transfer or medial patellofemoral ligament (MPFL) reconstruction in the young adult prevents further instability. Although these techniques are proven in the young adult, they may cause growth arrest and deformity where the physis is open. A vigorous non-operative strategy may permit delay of surgery until growth is complete. Where non-operative treatment has failed a modified MPFL reconstruction may be performed to maintain stability until physeal closure permits anatomical reconstruction. If significant growth remains an extraosseous reconstruction of the MPFL may impart the lowest risk to the physis. If minor growth remains image intensifier guided placement of femoral intraosseous fixation may impart a small, but acceptable, risk to the physis.

This paper presents and discusses the literature relating to adolescent instability and provides a framework for management of these patients.

Cite this article: Bone Joint J 2017;99-B:159–70.

Aims

The aim of this study was to compare the effectiveness of a femoral nerve block and a periarticular infiltration in the management of early post-operative pain after total knee arthroplasty (TKA).

Aims

Our aim was to examine the clinical and radiographic outcomes in 257 consecutive Oxford unicompartmental knee arthroplasties (OUKAs) (238 patients), five years post-operatively.

Aims

To present our experience of using a combination of intra-articular osteotomy and external fixation to treat different deformities of the knee.

Aims

It is widely held that most Baker’s cysts resolve after treatment of the intra-articular knee pathology. The present study aimed to evaluate the fate of Baker’s cysts and their associated symptoms after total knee arthroplasty (TKA).

We explored the literature surrounding whether allergy and hypersensitivity has a clinical basis for implant selection in total knee arthroplasty (TKA). In error, the terms hypersensitivity and allergy are often used synonymously. Although a relationship is present, we could not find any evidence of implant failure due to allergy. There is however increasing basic science that suggests a link between loosening and metal ion production. This is not an allergic response but is a potential problem. With a lack of evidence logically there can be no justification to use ‘hypoallergenic’ implants in patients who have pre-existing skin sensitivity to the metals used in TKA.

Cite this article: Bone Joint J 2016;98-B:437–41.

Objectives

Normal sagittal spine-pelvis-lower extremity alignment is crucial in humans for maintaining an ergonomic upright standing posture, and pathogenesis in any segment leads to poor balance. The present study aimed to investigate how this sagittal alignment can be affected by severe knee osteoarthritis (KOA), and whether associated changes corresponded with symptoms of lower back pain (LBP) in this patient population.

Instability is a common indication for early revision after both primary and revision total knee arthroplasty (TKA), accounting for up to 20% in the literature. The number of TKAs performed annually continues to climb exponentially, thus having an effective algorithm for treatment is essential. This relies on a thorough pre- and intra-operative assessment of the patient. The underlying cause of the instability must be identified initially and subsequently, the surgeon must be able to balance the flexion and extension gaps and be comfortable using a variety of constrained implants.

This review describes the assessment of the unstable TKA, and the authors’ preferred form of treatment for these difficult cases where the source of instability is often multifactorial.

Cite this article: Bone Joint J 2016;98-B(1 Suppl A):116–19.

We have investigated iatrogenic popliteal artery injuries (PAI) during non arthroplasty knee surgery regarding mechanism of injury, treatment and outcomes, and to identify successful strategies when injury occurs.

In all, 21 iatrogenic popliteal artery injuries in 21 patients during knee surgery other than knee arthroplasty were identified from the Swedish Vascular Registry (Swedvasc) between 1987 and 2011. Prospective registry data were supplemented with case-records, including long-term follow-up. In total, 13 patients suffered PAI during elective surgery and eight during urgent surgery such as fracture fixation or tumour resection. Nine injuries were detected intra-operatively, five within 12 to 48 hours and seven > 48 hours post-operatively (two days to 23 years).

There were 19 open vascular and two endovascular surgical repairs. Two patients died within six months of surgery. One patient required amputation. Only six patients had a complete recovery of whom had the vascular injury detected at time of injury and repaired by a vascular surgeon. Patients sustaining vascular injury during elective procedures are more likely to litigate (p = 0.029).

We conclude that outcomes are poorer when there is a delay of diagnosis and treatment, and that orthopaedic surgeons should develop strategies to detect PAI early and ensure rapid access to vascular surgical support.

Cite this article: Bone Joint J 2015;97-B:192–6.

Popliteal artery injury (PAI) is a feared complication during knee replacement. Our aim was to investigate those injuries that occurred in association with knee replacement in terms of the type of injury, treatment and outcomes.

From our national vascular registry (Swedvasc) and the Swedish Patient Insurance databases a total of 32 cases were identified. Prospective data from the registries was supplemented with case-records, including long-term follow-up.

We estimated the incidence during 1998 to 2010 to be 0.017%. In our series of 32 patients with PAI occurring between 1987 and 2011, 25 (78%) were due to penetrating trauma and seven were caused by blunt trauma. The patients presented in three ways: bleeding (14), ischaemia (7) and false aneurysm formation (11), and five occurred during revision surgery. A total of 12 injuries were detected intra-operatively, eight within 24 hours (3 to 24) and 12 at more than 24 hours post-operatively (2 to 90 days). Treatment comprised open surgery in 28 patients. Patency of the vascular repair at 30 days was 97% (31 of 32, one amputation). At the time of follow-up (median 546 days, mean 677 days (24 to 1251)), 25 patients had residual symptoms. Of seven patients with a complete recovery, six had had an early diagnosis of the PAI during the procedure, and were treated by a vascular surgeon in the same hospital.

PAI is a rare adverse event during knee replacement surgery. The outcome following such events is often adversely affected by diagnostic and therapeutic delay. Bleeding and false aneurysm were the most common clinical presentations.

Cite this article: Bone Joint J 2013;95-B:1645–9.

Objective

Mortality rates reported by the National Joint Registry for England and Wales (NJR) were higher following cemented total knee replacement (TKR) compared with uncemented procedures. The aim of this study is to examine and compare the effects of cemented and uncemented TKR on the activation of selected markers of inflammation, endothelium, and coagulation, and on the activation of selected cytokines involved in the various aspects of the systemic response following surgery.

The role of arthroscopy in the treatment of soft-tissue injuries associated with proximal tibial fractures remains debatable. Our hypothesis was that MRI over-diagnoses clinically relevant associated soft-tissue injuries. This prospective study involved 50 consecutive patients who underwent surgical treatment for a split-depression fracture of the lateral tibial condyle (AO/OTA type B3.1). The mean age of patients was 50 years (23 to 86) and 27 (54%) were female. All patients had MRI and arthroscopy. Arthroscopy identified 12 tears of the lateral meniscus, including eight bucket-handle tears that were sutured and four that were resected, as well as six tears of the medial meniscus, of which five were resected. Lateral meniscal injuries were diagnosed on MRI in four of 12 patients, yielding an overall sensitivity of 33% (95% confidence interval (CI) 11 to 65). Specificity was 76% (95% CI 59 to 88), with nine tears diagnosed among 38 menisci that did not contain a tear. MRI identified medial meniscal injuries in four of six patients, yielding an overall sensitivity of 67% (95% CI 24 to 94). Specificity was 66% (95% CI 50 to 79), with 15 tears diagnosed in 44 menisci that did not contain tears.

MRI appears to offer only a marginal benefit as the specificity and sensitivity for diagnosing meniscal injuries are poor in patients with a fracture. There were fewer arthroscopically-confirmed associated lesions than reported previously in MRI studies.

Cite this article: Bone Joint J 2014;96-B:1631–6.

Hypermobility is an acknowledged risk factor for patellar instability. In this case control study the influence of hypermobility on clinical outcome following medial patellofemoral ligament (MPFL) reconstruction for patellar instability was studied.

A total of 25 patients with hypermobility as determined by the Beighton criteria were assessed and compared with a control group of 50 patients who were matched for age, gender, indication for surgery and degree of trochlear dysplasia. The patients with hypermobility had a Beighton Score of ≥ 6; the control patients had a score of < 4. All patients underwent MPFL reconstruction performed using semitendinosus autograft and a standardised arthroscopically controlled technique. The mean age of the patients was 25 years (17 to 49) and the mean follow-up was 15 months (6 to 30).

Patients with hypermobility had a significant improvement in function following surgery, with reasonable rates of satisfaction, perceived improvement, willingness to repeat and likelihood of recommendation. Functional improvements were significantly less than in control patients (p < 0.01).

Joint hypermobility is not a contraindication to MPFL reconstruction although caution is recommended in managing the expectations of patients with hypermobility before consideration of surgery.

We compared the incidence and severity of complications during and after closing- and opening-wedge high tibial osteotomy used for the treatment of varus arthritis of the knee, and identified the risk factors associated with the development of complications. In total, 104 patients underwent laterally based closing-wedge and 90 medial opening-wedge high tibial osteotomy between January 1993 and December 2006. The characteristics of each group were similar. All the patients were followed up for more than 12 months. We assessed the outcome using the Hospital for Special Surgery knee score, and recorded the complications. Age, gender, obesity (body mass index > 27.5 kg/m²), the type of osteotomy (closing versus opening) and the pre-operative mechanical axis were subjected to risk-factor analysis.

The mean Hospital for Special Surgery score in the closing and opening groups improved from 73.4 (54 to 86) to 91.8 (81 to 100) and from 73.8 (56 to 88) to 93 (84 to 100), respectively. The incidence of complications overall and of major complications in both groups was not significantly different (p = 0.20 overall complication, p = 0.29 major complication). Logistic regression analysis adjusting for obesity and the pre-operative mechanical axis showed that obesity remained a significant independent risk factor (odds ratio = 3.23) of a major complication after high tibial osteotomy.

Our results suggest that the opening-wedge high tibial osteotomy can be an alternative treatment option for young patients with medial compartment osteoarthritis and varus deformity.

We have previously reported the short-term radiological results of a randomised controlled trial comparing kinematically aligned total knee replacement (TKR) and mechanically aligned TKR, along with early pain and function scores. In this study we report the two-year clinical results from this trial. A total of 88 patients (88 knees) were randomly allocated to undergo either kinematically aligned TKR using patient-specific guides, or mechanically aligned TKR using conventional instruments. They were analysed on an intention-to-treat basis. The patients and the clinical evaluator were blinded to the method of alignment.

At a minimum of two years, all outcomes were better for the kinematically aligned group, as determined by the mean Oxford knee score (40 (15 to 48) versus 33 (13 to 48); p = 0.005), the mean Western Ontario McMaster Universities Arthritis index (WOMAC) (15 (0 to 63) versus 26 (0 to 73); p = 0.005), mean combined Knee Society score (160 (93 to 200) versus 137 (64 to 200); p= 0.005) and mean flexion of 121° (100 to 150) versus 113° (80 to 130) (p = 0.002). The odds ratio of having a pain-free knee at two years with the kinematically aligned technique (Oxford and WOMAC pain scores) was 3.2 (p = 0.020) and 4.9 (p = 0.001), respectively, compared with the mechanically aligned technique. Patients in the kinematically aligned group walked a mean of 50 feet further in hospital prior to discharge compared with the mechanically aligned group (p = 0.044).

In this study, the use of a kinematic alignment technique performed with patient-specific guides provided better pain relief and restored better function and range of movement than the mechanical alignment technique performed with conventional instruments.

Cite this article: Bone Joint J 2014;96-B:907–13.

Objectives

Our objective in this article is to test the hypothesis that type 2 diabetes mellitus (T2DM) is a factor in the onset and progression of osteoarthritis, and to characterise the quality of the articular cartilage in an appropriate rat model.

This was a retrospective analysis of the medium- to long-term results of 46 TC3 Sigma revision total knee replacements using long uncemented stems in press-fit mode.

Clinical and radiological analysis took place pre-operatively, at two years post-operatively, and at a mean follow-up of 8.5 years (4 to 12). The mean pre-operative International Knee Society (IKS) clinical score was 42 points (0 to 74), improving to 83.7 (52 to 100) by the final follow-up. The mean IKS score for function improved from 34.3 points (0 to 80) to 64.2 (15 to 100) at the final follow-up. At the final follow-up 30 knees (65.2%) had an excellent result, seven (15.2%) a good result, one (2.2%) a medium and eight (17.4%) a poor result. There were two failures, one with anteroposterior instability and one with aseptic loosening.

The TC3 revision knee system, when used with press-fit for long intramedullary stems and cemented femoral and tibial components, in both septic and aseptic revisions, results in a satisfactory clinical and radiological outcome, and has a good medium- to long-term survival rate.

Between 2003 and 2007, 99 knees in 77 patients underwent opening wedge high tibial osteotomy. We evaluated the effect of initial stable fixation combined with an artificial bone substitute on the mid- to long-term outcome after medial opening-wedge high tibial osteotomy (HTO) for medial compartmental osteoarthritis or spontaneous osteonecrosis of the knee in 78 knees in 64 patients available for review at a minimum of five years (mean age 68 years; 49 to 82). The mean follow-up was 6.5 years (5 to 10). The mean Knee Society knee score and function score improved from 49.6 (sd 11.4, 26 to 72) and 56.6 (sd 15.6, 5 to 100) before surgery to 88.1 (sd 12.5, 14 to 100) and 89.4 (sd 15.6, 5 to 100) at final follow-up (p <  0.001) respectively. There were no significant differences between patients aged ≥ 70 and < 70 years. The mean standing femorotibial angle was corrected significantly from 181.7° (sd 2.7°, 175° to 185°) pre-operatively to 169.7° (sd 2.4°, 164° to 175°) at one year’s follow-up (p < 0.001) and 169.6° (sd 3.0°, 157° to 179°) at the final follow-up (p = 0.69 vs one year).

Opening-wedge HTO using a stable plate fixation system combined with a bone substitute is a reliable procedure that provides excellent results. Although this treatment might seem challenging for older patients, our results strongly suggest that the results are equally good.

Cite this article: Bone Joint J 2014;96-B:339–44.

Isolated patellofemoral arthritis is a common condition and there are varying opinions on the most effective treatments. Non-operative and operative treatments have failed to demonstrate effective long-term treatment for those in an advanced stage of the condition. Newer designs and increased technology in patellofemoral replacement (PFR) have produced more consistent outcomes. This has led to a renewed enthusiasm for this procedure. Newer PFR prostheses have addressed the patellar maltracking issues plaguing some of the older designs. Short-term results with contemporary prostheses and new technology are described here.

Cite this article: Bone Joint J 2013;95-B, Supple A:124–8.

Most patients (95%) with fibular hemimelia have an absent anterior cruciate ligament (ACL). The purpose of this study was to assess the long-term outcome of such patients with respect to pain and knee function. We performed a retrospective review of patients with fibular hemimelia and associated ACL deficiency previously treated at our institution. Of a possible 66 patients, 23 were sent the Musculoskeletal Outcomes Data Evaluation and Management System (MODEMS) questionnaire and Lysholm knee score to complete. In all, 11 patients completed the MODEMS and nine completed the Lysholm score questionnaire. Their mean age was 37 years (27 to 57) at review. Five patients had undergone an ipsilateral Symes amputation. There was no significant difference in any subsections of the Short-Form 36 scores of our patients compared with age-matched controls. The mean Lysholm knee score was 90.2 (82 to 100). A slight limp was reported in six patients. No patients had episodes of locking of the knee or required a supportive device for walking. Four had occasional instability with sporting activities.

These results suggest that patients with fibular hemimelia and ACL deficiency can live active lives with a similar health status to age-matched controls.

Mobile-bearing unicompartmental knee replacements (UKRs) with a flat tibial plateau have not performed well in the lateral compartment, owing to a high dislocation rate. This led to the development of the Domed Lateral Oxford UKR (Domed OUKR) with a biconcave bearing. The aim of this study was to assess the survival and clinical outcomes of the Domed OUKR in a large patient cohort in the medium term.

We prospectively evaluated 265 consecutive knees with isolated disease of the lateral compartment and a mean age at surgery of 64 years (32 to 90). At a mean follow-up of four years (sd 2.2, (0.5 to 8.3)) the mean Oxford knee score was 40 out of 48 (sd 7.4). A total of 12 knees (4.5%) had re-operations, of which four (1.5%) were for dislocation. All dislocations occurred in the first two years. Two (0.8%) were secondary to significant trauma that resulted in ruptured ligaments, and two (0.8%) were spontaneous. In four patients (1.5%) the UKR was converted to a primary TKR. Survival at eight years, with failure defined as any revision, was 92.1% (95% confidence interval 81.3 to 100).

The Domed Lateral OUKR gives good clinical outcomes, low re-operation and revision rates and a low dislocation rate in patients with isolated lateral compartmental disease, in the hands of the designer surgeons.

Cite this article: Bone Joint J 2014;96-B:59–64.

Patients with skeletal dysplasia are prone to developing advanced osteoarthritis of the knee requiring total knee replacement (TKR) at a younger age than the general population. TKR in this unique group of patients is a technically demanding procedure owing to the deformity, flexion contracture, generalised hypotonia and ligamentous laxity. We retrospectively reviewed the outcome of 11 TKRs performed in eight patients with skeletal dysplasia at our institution using the Stanmore Modular Individualised Lower Extremity System (SMILES) custom-made rotating-hinge TKR. There were three men and five women with mean age of 57 years (41 to 79). Patients were followed clinically and radiologically for a mean of seven years (3 to 11.5). The mean Knee Society clinical and function scores improved from 24 (14 to 36) and 20 (5 to 40) pre-operatively, respectively, to 68 (28 to 80) and 50 (22 to 74), respectively, at final follow-up. Four complications were recorded, including a patellar fracture following a fall, a tibial peri-prosthetic fracture, persistent anterior knee pain, and aseptic loosening of a femoral component requiring revision. Our results demonstrate that custom primary rotating-hinge TKR in patients with skeletal dysplasia is effective at relieving pain, with a satisfactory range of movement and improved function. It compensates for bony deformity and ligament deficiency and reduces the likelihood of corrective osteotomy. Patellofemoral joint complications are frequent and functional outcome is worse than with primary TKR in the general population.

Although it has been suggested that the outcome after revision of a unicondylar knee replacement (UKR) to total knee replacement (TKR) is better when the mechanism of failure is understood, a comparative study on this subject has not been undertaken.

A total of 30 patients (30 knees) who underwent revision of their unsatisfactory UKR to TKR were included in the study: 15 patients with unexplained pain comprised group A and 15 patients with a defined cause for pain formed group B. The Oxford knee score (OKS), visual analogue scale for pain (VAS) and patient satisfaction were assessed before revision and at one year after revision, and compared between the groups.

The mean OKS improved from 19 (10 to 30) to 25 (11 to 41) in group A and from 23 (11 to 45) to 38 (20 to 48) in group B. The mean VAS improved from 7.7 (5 to 10) to 5.4 (1 to 8) in group A and from 7.4 (2 to 9) to 1.7 (0 to 8) in group B. There was a statistically significant difference between the mean improvements in each group for both OKS (p = 0.022) and VAS (p = 0.002). Subgroup analysis in group A, performed in order to define a patient factor that predicts outcome of revision surgery in patients with unexplained pain, showed no pre-operative differences between both subgroups.

These results may be used to inform patients about what to expect from revision surgery, highlighting that revision of UKR to TKR for unexplained pain generally results in a less favourable outcome than revision for a known cause of pain.

Cite this article: Bone Joint J 2013;95-B:1204–8.

In this paper, we will consider the current role of simultaneous-bilateral TKA. Based on available evidence, it is our opinion that bilateral one stage TKR is a safe and efficacious treatment for patients with severe bilateral arthritic knee disease but should be reserved for selected patients without significant medical comorbidities.

In this paper, we will consider the current role of simultaneous-bilateral TKA. Based on available evidence, it is our opinion that simultaneous bilateral TKA carries a higher risk of morbidity and mortality and should be reserved for select few.

We present the ten- to 15-year follow-up of 31 patients (34 knees), who underwent an Elmslie-Trillat tibial tubercle osteotomy for chronic, severe patellar instability, unresponsive to non-operative treatment. The mean age of the patients at the time of surgery was 31 years (18 to 46) and they were reviewed post-operatively, at four years (2 to 8) and then at 12 years (10 to 15). All patients had pre-operative knee radiographs and Cox and Insall knee scores. Superolateral portal arthroscopy was performed per-operatively to document chondral damage and after the osteotomy to assess the stability of the patellofemoral joint. A total of 28 knees (82%) had a varying degree of damage to the articular surface. At final follow-up 25 patients (28 knees) were available for review and underwent clinical examination, radiographs of the knee, and Cox and Insall scoring. Six patients who had no arthroscopic chondral abnormality showed no or only early signs of osteoarthritis on final radiographs; while 12 patients with lower grade chondral damage (grade 1 to 2) showed early to moderate signs of osteoarthritis and six out of ten knees with higher grade chondral damage (grade 3 to 4) showed marked evidence of osteoarthritis; four of these had undergone a knee replacement. In the 22 patients (24 knees) with complete follow-up, 19 knees (79.2%) were reported to have a good or excellent outcome at four years, while 15 knees (62.5%) were reported to have the same at long-term follow-up. The functional and radiological results show that the extent of pre-operatively sustained chondral damage is directly related to the subsequent development of patellofemoral osteoarthritis.

Cite this article: Bone Joint J 2013;95-B:478–85.

We systematically reviewed the published literature on the complications of closing wedge high tibial osteotomy for the treatment of unicompartmental osteoarthritis of the knee. Publications were identified using the Cochrane Library, MEDLINE, EMBASE and CINAHL databases up to February 2012. We assessed randomised (RCTs), controlled group clinical (CCTs) trials, case series in publications associated with closing wedge osteotomy of the tibia in patients with osteoarthritis of the knee and finally a Cochrane review. Many of these trials included comparative studies (opening wedge versus closing wedge) and there was heterogeneity in the studies that prevented pooling of the results.

In this paper, we consider wound healing after total knee arthroplasty.

Seven stiff total knee arthroplasties are presented to illustrate the roles of: 1) manipulation under general anesthesia; 2) multiple concurrent diagnoses in addition to stiffness; 3) extra-articular pathology; 4) pain as part of the stiffness triad (pain and limits to flexion or extension); 5) component internal rotation; 6) multifactorial etiology; and 7) surgical exposure in this challenging clinical problem.

We report a prospective analysis of clinical outcome in patients treated with medial patellofemoral ligament (MPFL) reconstruction using an autologous semitendinosus graft. The technique includes superolateral portal arthroscopic assessment before and after graft placement to ensure correct graft tension and patellar tracking before fixation. Between October 2005 and October 2010, a total of 201 consecutive patients underwent 219 procedures. Follow-up is presented for 211 procedures in 193 patients with a mean age of 26 years (16 to 49), and mean follow-up of 16 months (6 to 42). Indications were atraumatic recurrent patellar dislocation in 141 patients, traumatic recurrent dislocation in 50, pain with subluxation in 14 and a single dislocation with persistent instability in six. There have been no recurrent dislocations/subluxations. There was a statistically significant improvement between available pre- and post-operative outcome scores for 193 patients (all p < 0.001). Female patients with a history of atraumatic recurrent dislocation and all patients with history of previous surgery had a significantly worse outcome (all p < 0.05). The indication for surgery, degree of dysplasia, associated patella alta, time from primary dislocation to surgery and evidence of associated cartilage damage at operation did not result in any significant difference in outcome.

This series adds considerably to existing evidence that MPFL reconstruction is an effective surgical procedure for selected patients with patellofemoral instability.

We report the outcome of 32 patients (37 knees) who underwent hemicallostasis with a dynamic external fixator for osteoarthritis of the medial compartment of the knee. There were 16 men (19 knees) and 16 women (18 knees) with a mean age at operation of 54.6 years (27 to 72). The aim was to achieve a valgus overcorrection of 2° to 8° or mechanical axis at 62.5% (± 12.5%). At a mean follow-up of 62.8 months (51 to 81) there was no change in the mean range of movement, and no statistically significant difference in the Insall-Salvati index or tibial slope (p = 0.11 and p = 0.15, respectively). The mean hip-knee-ankle angle changed from 190.6 (183° to 197°) to 176.0° (171° to 181°), with a mean final position of the mechanical axis of 58.5% (35.1% to 71.2%).

The desired alignment was attained in 31 of 37 (84%) knees. There were 21 excellent, 13 good, two fair and one poor result according to the Oxford knee score with no correlation between age and final score. This score was at its best at one year with a statistically significant deterioration at two years (p = 0.001) followed by a small but not statistically significant deterioration until the final follow-up (p = 0.17). All the knees with Ahlback grade 1 osteoarthritis had excellent or good results. Complications included pin tract infections involving 16.4% of all pins used, delayed union in two, knee stiffness in four, fracture of the lateral cortex in one and ring sequestrum in one.

In conclusion, hemicallostasis provides precision in attaining the desired alignment without interfering with tibial slope or patellar height, and is relatively free of serious complications.

Pulmonary embolism is a serious complication after arthroscopy of the knee, about which there is limited information. We have identified the incidence and risk factors for symptomatic pulmonary embolism after arthroscopic procedures on outpatients. The New York State Department of Health Statewide Planning and Research Cooperative System database was used to review arthroscopic procedures of the knee performed on outpatients between 1997 and 2006, and identify those admitted within 90 days of surgery with an associated diagnosis of pulmonary embolism. Potential risk factors included age, gender, complexity of surgery, operating time defined as the total time that the patient was actually in the operating room, history of cancer, comorbidities, and the type of anaesthesia. We identified 374 033 patients who underwent 418 323 outpatient arthroscopies of the knee. There were 117 events of pulmonary embolism (2.8 cases for every 10 000 arthroscopies). Logistic regression analysis showed that age and operating time had significant dose-response increases in risk (p < 0.001) for a subsequent admission with a pulmonary embolism. Female gender was associated with a 1.5-fold increase in risk (p = 0.03), and a history of cancer with a threefold increase (p = 0.05).

These risk factors can be used when obtaining informed consent before surgery, to elevate the level of clinical suspicion of pulmonary embolism in patients at risk, and to establish a rationale for prospective studies to test the clinical benefit of thromboprophylaxis in high-risk patients.

The administration of intra-articular local anaesthetic is common following arthroscopy of the knee. However, recent evidence has suggested that bupivacaine may be harmful to articular cartilage. This study aimed to establish whether infiltration of bupivacaine around the portals is as effective as intra-articular injection.

We randomised 137 patients to receive either 20 ml 0.5% bupivacaine introduced into the joint (group 1) or 20 ml 0.5% bupivacaine infiltrated only around the portals (group 2) following arthroscopy. A visual analogue scale was administered one hour post-operatively to assess pain relief. Both patients and observers were blinded to the treatment group. A power calculation was performed.

The mean visual analogue score was 3.24 (sd 2.20) in group I and 3.04 (sd 2.31) in group 2. This difference was not statistically significant (p = 0.62).

Infiltration of bupivacaine around the portals had an equivalent effect on pain scores at one hour, and we would therefore recommend this technique to avoid the possible chondrotoxic effect of intra-articular bupivacaine.

We randomised 62 knees to receive either cemented or cementless versions of the Oxford unicompartmental knee replacement. The implants used in both arms of the study were similar, except that the cementless components were coated with porous titanium and hydroxyapatite. The tibial interfaces were studied with fluoroscopically-aligned radiographs.

At one year there was no difference in clinical outcome between the two groups. Narrow radiolucent lines were seen at the bone-implant interfaces in 75% of cemented tibial components. These were partial in 43%, and complete in 32%. In the cementless implants, partial radiolucencies were seen in 7% and complete radiolucencies in none. These differences are statistically significant (p < 0.0001) and imply satisfactory bone ingrowth into the cementless implants.

We compared the results of 146 patients who received an anatomic modular knee fixed-bearing total knee replacement (TKR) in one knee and a low contact stress rotating platform mobile-bearing TKR in the other. There were 138 women and eight men with a mean age of 69.8 years (42 to 80). The mean follow-up was 13.2 years (11.0 to 14.5). The patients were assessed clinically and radiologically using the rating systems of the Hospital for Special Surgery and the Knee Society at three months, six months, one year, and annually thereafter.

The assessment scores of both rating systems pre-operatively and at the final review did not show any statistically significant differences between the two designs of implant. In the anatomic modular knee group, one knee was revised because of aseptic loosening of the tibial component and one because of infection. In addition, three knees were revised because of wear of the polyethylene tibial bearing. In the low contact stress group, two knees were revised because of instability requiring exchange of the polyethylene insert and one because of infection.

The radiological analysis found no statistical difference in the incidence of radiolucent lines at the final review (Student’s t-test, p = 0.08), most of which occurred at tibial zone 1. The Kaplan-Meier survivorship for aseptic loosening of the anatomic modular knee and the low contact stress implants at 14.5 years was 99% and 100%, respectively, with a 95% confidence interval of 94% to 100% for both designs.

We found no evidence of the superiority of one design over the other at long-term follow-up.

We report the mid-term results of a new patellofemoral arthroplasty for established isolated patellofemoral arthritis. We have reviewed the experience of 109 consecutive patellofemoral resurfacing arthroplasties in 85 patients who were followed up for at least five years.

The five-year survival rate, with revision as the endpoint, was 95.8% (95% confidence interval 91.8% to 99.8%). There were no cases of loosening of the prosthesis. At five years the median Bristol pain score improved from 15 of 40 points (interquartile range 5 to 20) pre-operatively, to 35 (interquartile range 20 to 40), the median Melbourne score from 10 of 30 points (interquartile range 6 to 15) to 25 (interquartile range 20 to 29), and the median Oxford score from 18 of 48 points (interquartile range 13 to 24) to 39 (interquartile range 24 to 45). Successful results, judged on a Bristol pain score of at least 20 at five years, occurred in 80% (66) of knees. The main complication was radiological progression of arthritis, which occurred in 25 patients (28%) and emphasises the importance of the careful selection of patients. These results give increased confidence in the use of patellofemoral arthroplasty.

We assessed the functional outcome following fracture of the tibial plateau in 63 consecutive patients. Fifty-one patients were treated by internal fixation, five by combined internal and external fixation and seven non-operatively. Measurements of joint movement and muscle function were made using a muscle dynamometer at three, six and 12 months following injury. Thirteen patients (21%) had a residual flexion contracture at one year. Only nine (14%) patients achieved normal quadriceps muscle strength at 12 months, while 19 (30%) achieved normal hamstring muscle strength. Recovery was significantly slower in patients older than 40 years of age. We conclude that there is significant impairment of movement and muscle function after fracture of the tibial plateau and that the majority of patients have not fully recovered one year after injury.

A prospective, randomised, controlled trial compared two different techniques of high tibial osteotomy with a lateral closing wedge or a medial opening wedge, stabilised by a Puddu plate. The clinical outcome and radiological results were examined at one year.

The primary outcome measure was the achievement of an overcorrection of valgus of 4°. Secondary outcome measures were the severity of pain (visual analogue scale), knee function (Hospital for Special Surgery score), and walking distance.

Between January 2001 and April 2004, 92 patients were randomised to one or other of the techniques. At follow-up at one year the post-operative hip-knee-ankle angle was 3.4° (± 3.6° sd) valgus after a closing wedge and 1.3° (± 4.7° sd) of valgus after an opening wedge. The adjusted mean difference of 2.1° was significant (p = 0.02). The deviation from 4° of valgus alignment was 2.7° (± 2.4° sd) in the closing wedge and 4.0° (± 3.6° sd) in the opening-wedge groups. The adjusted mean difference of 1.67° was also significant (p = 0.01).

The severity of pain, knee score and walking ability improved in both groups, but the difference was not significant.

Because of pain, the staples required removal in 11 (23%) patients in the closing-wedge group and a Puddu plate was removed in 27 (60%) patients in the opening-wedge group. This difference was significant (p < 0.001).

We conclude that closing-wedge osteotomy achieves a more accurate correction with less morbidity, although both techniques had improved the function of the knee at one year after the procedure.

The clinical results of bilateral total knee replacement staged at a one-week interval during a single hospital admission were compared with bilateral total knee replacements performed under the same anaesthetic and with bilateral total knee replacements performed during two separate admissions. The data were retrospectively reviewed. All operations had been performed by the same surgeon using the same design of prosthesis at a single institution.

The operative time and length of stay for the one-week staged group were comparable with those of the separate admission group but longer than for the patients treated under one anaesthetic. There was a low rate of complications and good clinical outcome in all groups at a mean follow-up of four years (1 to 7.2). The group staged at a one-week interval had the least blood loss (p = 0.004).

With appropriate patient selection, bilateral total knee replacement performed under a single anaesthetic, or staged at a one-week interval, is a safe and effective method to treat bilateral arthritis of the knee.

We carried out an audit on the result of achieving early walking in total knee replacement after instituting a new rehabilitation protocol, and assessed its influence on the development of deep-vein thrombosis as determined by Doppler ultrasound scanning on the fifth post-operative day. Early mobilisation was defined as beginning to walk less than 24 hours after knee replacement.

Between April 1997 and July 2002, 98 patients underwent a total of 125 total knee replacements. They began walking on the second post-operative day unless there was a medical contraindication. They formed a retrospective control group. A protocol which allowed patients to start walking at less than 24 hours after surgery was instituted in August 2002. Between August 2002 and November 2004, 97 patients underwent a total of 122 total knee replacements. They formed the early mobilisation group, in which data were prospectively gathered. The two groups were of similar age, gender and had similar medical comorbidities. The surgical technique and tourniquet times were similar and the same instrumentation was used in nearly all cases. All the patients received low-molecular-weight heparin thromboprophylaxis and wore compression stockings post-operatively.

In the early mobilisation group 90 patients (92.8%) began walking successfully within 24 hours of their operation. The incidence of deep-vein thrombosis fell from 27.6% in the control group to 1.0% in the early mobilisation group (chi-squared test, p < 0.001). There was a difference in the incidence of risk factors for deep-vein thrombosis between the two groups. However, multiple logistic regression analysis showed that the institution of an early mobilisation protocol resulted in a 30-fold reduction in the risk of post-operative deep-vein thrombosis when we adjusted for other risk factors.