Background: Arthroscopic menisectomy is one of the most commonly performed procedures in the NHS, yet there is no recent review of contemporary knee arthroscopy for meniscal tears or comparisons of tear morphology and clinical findings. We aim to address this problem with a large, prospective longitudinal study.

Aims: The aims of this study were to examine the anatomical location and morphology of meniscal tears encountered at arthroscopy and to correlate this to the clinical findings.

Method: Data on 775 consecutive patients undergoing knee arthroscopy by a single surgeon between 1994 and 2004 was prospectively collected. Clinical data included age, sex, history of trauma, joint line tenderness and presence of an effusion. Meniscal tears were arthroscopically classified by site (medial/lateral, anterior/middle/posterior) and type (flap, horizontal cleavage, bucket-handle, radial, degenerative and other).

Results: Data was complete for 724 patients (517 male and 207 female [m:f 2.5:1]). The mean age was 48 years (range 10 to 87 years). Mean duration of symptoms was 8 months.

54% of meniscal tears were medial, 12% lateral and 10% bilateral. Patients with a lateral tear were significantly younger (45 Vs 51 yrs, p< 0.001).

The most common type of medial tear was a flap tear (34%), followed by horizontal cleavage tears [HCT] (18%). The posterior 1/3 is the most common position. Laterally the tear morphology shows HCT comprising 25% and degenerative tears 17%, with the most common position a middle 1/3 tear. Lateral tears are more common in females (p< 0.05)

Patients with bucket handle tears were significantly younger (41 Vs 53yrs, p< 0.001) and more likely to have a history of trauma (p< 0.001). Medial joint line tenderness was the most sensitive test (79%) and had the highest positive predictive value (81%). McMurry’s test is the most specific for both medial and lateral tears (90%) but is not sensitive. Medial meniscal tears are more accurately diagnosed clinically than lateral (79% Vs 50%).

Conclusion: Meniscal tears are a common pathology, particularly on the medial side. Morphology and position of tears vary as to which side the tear is. Clinical details can help determine the type of tear found with clinical examination being more accurate for medial meniscal tears.

The principles of revision total knee replacement are to understand the cause of failure, adequate surgical exposure, achieving appropriate soft tissue balance, restoration of limb and joint line alignment, correct implant alignment, and a good range of motion. It is a technically and economically demanding procedure and its successful performance requires thorough preoperative planning, adherence to the principles, availability of diverse implant options and adequate bone graft.

We prospectively assessed the survivorship of Co-ordinate Ultra prosthesis (DePuy, Warsaw, Ind) used for revision knee arthroplasty. Forty-nine patients had 53 revision knee replacements performed by the senior author between April 1999 and September 2001. Seven patients (7 knees) had died. At a mean follow-up of 6 years (range: 5–7 years), 46 knees in 42 patients were available for review. None were lost to follow-up. There were 31 women and 11 men, with a mean age of 74.2 years. The reason for revision was instability in 39 knees, infection in 3 knees, pain in 2 knees and stiffness in 2 knees.

Significant improvement was noted in the SF-12 PCS and WOMAC pain and stiffness scores at the latest follow-up. None of these patients required re-revision. None of the knees showed evidence of progressive loosening. Radio-opaque lines were found around the stems and were present in immediate post-operative radiographs; this did not indicate loosening or infection on further follow-up. Cumulative survival analysis (Kaplan-Meier method) was 100% at 7 years.

Clinical and radiological outcome analysis has revealed that the Co-ordinate Ultra revision knee system continues to function satisfactorily at a mean follow-up of 6 years.

Introduction: Reinfusion drains are used to minimise the need for allogenic blood transfusion, and its potential complications. Tranexamic acid {TA} is an antifibrinolytic agent that is used to decrease blood loss in total knee arthroplasty surgery. The effect of TA on reinfusion volume of drained blood has received little attention. The aim of our study is to measure the effect of TA on reinfusion volumes in primary total knee replacement {TKR}.

Methods: A cohort of consecutive patients undergoing primary total knee replacement between November 2006 and January 2008 were studied. Each patient was operated upon by the same surgeon, and had the same pros-thesis inserted. Patients operated upon before June 2007 did not receive TA but had reinfusion drains, while those who underwent surgery after June 2007 received TA along with the reinfusion drain. We measured pre and post operative haemoglobin {Hb}, drainage volume and reinfusion volume. The need for allogenic blood transfusion was recorded. TA and non TA groups were compared.

Results: Seventy patients were included in the study. There was no significant difference between the TA and non TA groups in pre operative Hb {13.2, 13.1g/dl} or post operative Hb {10.95, 10.9}. There was a significantly lower drainage volume {250 v 600ml} and subsequent reinfusion volume {100 v 465ml} in the TA group versus non TA groups respectively. There were no cases of thromboembolism or allogenic blood transfusion in either group.

Conclusion: Tranexamic acid significantly decreased post operative blood loss and subsequent reinfusion volumes in TKR. TA and reinfusion drains greatly decrease the demand for allogenic blood transfusion. Drainage volume is so low when TA is used in routine primary TKR, that the need for reinfusion drains is questionable. TA is cost-effective compared to reinfusion drains in TKR.

A consecutive group of 150 patients undergoing primary TKA performed by a single surgeon using single prosthesis were studied prospectively. The purpose of this study was to compare the clinical and radiographic results of TKA in obese and non-obese patients.

The patients were categorized into two groups: non-obese (body mass index (BMI < 30 kg/m2) and obese (BMI > 30 to 40 kg/m2). The Primary outcome measures: SF-12 and WOMAC scores were used as generic outcome measures, and the Knee Society scores were used to assess clinical outcome of TKA. The scores were done pre-operatively and at 1, 3 and 5 years post-operatively. Secondary outcome measures included patellar position, anterior knee pain, infections, revision rates, deep-vein thrombosis and pulmonary embolism, length of hospital stay and mortality.

Seventeen patients have died since and none were lost to follow-up. Obese patients had less benefit and overall KSS outcome scores at one year (p-value 0.05) but had similar scores at 3 and 5 years (p-values 0.3 and 0.5). Pre-operative WOMAC and SF-12 scores were significantly worst in obese patients (p-value 0.009 and 0.005) but had the similar outcome at 1, 3 and 5 years. Three patients in the series required revision surgery for infection. One patient had DVT and another had PE post-operatively.

Overall obese patients although had lower KSS scores at one year but had better outcome in SF-12 and WOMAC scores at one year. There was no difference at 3 and 5 years. We found that body weight did not influence adversely the outcome of TKA at medium term.

Introduction: The principles of revision arthroplasty are to understand the cause of failure, adequate surgical exposure, restoration of limb alignment, achieving appropriate soft tissue balance, correct implant alignment, restoration of joint line and a good range of motion. Revision knee Arthroplasty is a technically and economically demanding procedure and its successful performance requires thorough preoperative planning, adherence to the principles, availability of diverse implant options and adequate bone graft.

Aim: We prospectively assessed the survivorship of Coordinate Ultra prosthesis (DePuy, Warsaw, Ind) used for revision knee arthroplasty.

Materials and Methods: Fifty-three patients had revision knee replacement performed by the senior author between April 1999 and September 2001. Seven patients (7 knees) had died. At a mean follow-up of 6 years (range: 5–7years), 46 knees in 42 patients were available for review. None were lost to follow-up. There were 31 women and 11 men, with a mean age of 74.2 years. The reason for revision was instability in 39 knees, infection in 3 knees, pain in 2 knees and stiffness in 2 knees.

Results: Significant improvement was noted in the SF-12 PCS and WOMAC pain and stiffness scores at the latest follow-up. None of these patients required re-revision. Radiological evaluation was done using the Knee Society system. None of the knees showed evidence of progressive loosening. Radiopaque lines were found around the stems and were present in immediate post-operative radiographs; this did not indicated loosening or infection on further follow-up. Cumulative survival analysis (Kaplan Meier method) was 100% at 7 years.

Conclusion: Clinical and radiological outcome analysis has revealed that the Co-ordinate Ultra revision knee system continues to function satisfactorily at a mean follow-up of 6 years.

Introduction: Restoring normal mechanical axis is one of the key goals of the total knee arthroplasty (TKA). The majority of the surgeons resect the tibia perpendicular to its axis in the coronal plane, then use an intra-medullary jig inserted through the centre of the knee or slightly medial to centre of the knee to resect the distal femur at a 6 or 7degree valgus angle. The aim was to establish the safety of using a predetermined valgus angle (VA) and entry point (EP) in the primary TKA. We also studied the relationship between the VA and EP to the height, weight and BMI of the patient.

Materials and Methods: We studied 125 long leg radiographs of 125 patients who underwent TKA under the care of senior author. All the radiographs were taken in the preoperative clinic with knee in full extension and patella facing forward. The radiographs were used to measure the valgus angle and entry point of the femur. The patients with VA between 6–7 degrees and EP at the centre were defined as normal group and rest were defined as outliers.

Results: The VA ranged from 4 to 9.5 degrees (with a mean of 6.8 and SD 1.11). Only 66 (53%) knees had the VA between 6 and 7 degrees. The EP ranged from 30mm medial to 18mm lateral to the centre of the knee with a mean of 7.7mm medial to the centre of the knee (SD 6.1). The EP was at the centre of the knee in 31 (24.8%) knees and lateral to the centre in 19 (15.2%) knees. Only 14 (11.2%) knees were in the normal group. Overall there was no significant relationship between the EP and VA to the height, weight or BMI of the patient at p-value > 0.001.

Conclusions: The resection of distal femur using the predetermined valgus angle, the predetermined entry point is not a safe practice in TKA. The long leg radiographs of the knee should be studied to identify the outliers. In future computer-assisted surgery and digitalisation of the images may obviate the need for this. However, it may be prudent though to use pre-operative templating of long leg radiographs during the learning curve of computer assisted surgery as well.

Background and objectives: Total knee replacement (TKR) produces severe postoperative pain. Peripheral nerve blocks can be used as analgesic adjuncts after TKR. The use of peripheral nerve block has certainly reduced the use of opiates by 50%; however adding the sciatic nerve block to the femoral nerve block is controversial. The aim of this study was to compare femoral and femoral plus sciatic nerve blocks in postoperative pain management of patients undergoing TKR.

Materials and Methods: Total of 42 patients were studied. Twenty patients with an average of 75yrs (51–86yrs) received femoral nerve block alone. Twenty-two patients with an average age of 69yrs (53–83yrs) received femoral plus sciatic nerve block. 0.5% Chirocaine was used for nerve blocks. There was no significant difference between two groups in terms of pre-operative pain, pre-operative deformity, ROM and patella replaced. The primary outcome measures used were visual analogue scale (VAS) pain scores at 24 hours, 48 hours and 72 hours after the surgery. The amount of opiate consumption and PCA (patient controlled analgesia) used were also recorded. The secondary outcomes were postoperative nausea and vomiting, straight leg raise, neurological deficit, knee flexion, independent mobility and discharge from the hospital.

Results: The results showed significant decrease in the amount of pain in the femoral nerve block group than the combined nerve block patients. Patients who had combined nerve block complained of heaviness in the legs and were slow to mobilise. There was no significant difference in consumption of opiates, use of PCA, nausea and vomiting, independent mobility and the time of discharge from the hospital between the two groups.

Conclusion: The addition of sciatic nerve block to the femoral nerve block does not provide any additional benefits in TKR.

Introduction: The technique of quadriceps sparing knee arthroplasty involves a pure capsular incision, without violation of the extensor mechanism. This capsular incision should be placed distal to Vastus Medialis Obliquus (VMO). The termination of VMO is variable and may make the quadriceps sparing approach difficult. We initiated this study based on the hypothesis that quadriceps sparing approach may not be possible in all the patients undergoing total knee arthroplasty. We examined MRI scans of the knee joint to assess the variation in VMO muscle insertion in relation to the patella and variation of VMO muscle insertion in relation to the age.

Material and Methods: Between Jan 2005 and Dec 2005, 262 MRI scans of the knee joint were performed at our institute. We studied MRI scans of the patients aged 16 years and over. The scans with neoplasm or those without complete set of films were excluded from the study. There were 198 scans available for analysis. Our cohort consisted of 106 female patients and 92 male patients with an average age of 43 years (range 16–86 years). One hundred and thirty four patients were aged less than 50 years and 64 patients were 50 years or older.

We measured patellar height, VMO length on the axial views of the scans. The VMO insertion was calculated from the data and we divided the patients into proximal and distal groups in relation to the VMO termination on the patella. The proximal group included patients with VMO termination proximal to the mid-point of the patella and distal group included patients with VMO termination at or distal to the mid-point of the patella.

Results: The median height of the patella in female patients was 32mm (range 24–44mm) and in male patients was 36mm (range 28–48mm). The VMO length from the apex of the patella was 13.5mm (range 4–28mm) in female patients and 16mm (range 8–32mm) in male patients. Overall there were 119 (60%) patients in the proximal group and 79 (40%) in the distal group. In 20% of patients aged more than 50 years, VMO terminated in the distal half of the patella. In patients less than 50 years old, 50% had the VMO termination in the distal half of patella. A statistically significant inverse relationship was noted between the level of insertion of VMO and the age of the patient (p-value > 0.001, Chi-square test). There was no statistically significant relation between the level of insertion of VMO and the sex of the patient, in either age group (p-value 0.339).

Conclusion: Younger patients are statistically more likely to have a VMO which terminated at or more distal to the mid-point of patella. Therefore, the quadriceps sparing approach may not be possible in these subjects, however it is possible in majority of older patients.

Introduction: The technique of quadriceps sparing knee arthroplasty involves a pure capsular incision, without violation of the extensor mechanism. This capsular incision should be placed distal to Vastus Medialis Obliquus (VMO). It is well known that the termination of VMO is variable and may make the quadriceps sparing approach difficult. We initiated this study based on the hypothesis that the quadriceps sparing approach is not possible in all patients undergoing total knee arthroplasty.

Methods: We examined the axial MRI images of the knee joint performed over a period of 12 months at our institute. A total of 198 MRI scans were analysed between two observers.

To calculate the patellar height the apex of the patella was considered as ‘Reference Slice 1’. The consecutive slices were followed distally to the last slice in which the patella was visible. From ‘Reference Slice 1’ VMO muscle was followed distally to the slice in which the muscle was last visible. We calculated the patella height and VMO muscle length as the product of the number of MRI slices and MRI slice thickness.

Results: Of the 134 patients aged less than 50 years, 68 patients (50.7%) had a VMO that terminated in the proximal half of the patella. Out of 64 patients aged 50 years or older, 51 patients (79.7%) had a VMO that terminated in the proximal half of the patella.

A statistically significant inverse relationship was noted between the level of insertion of VMO and the age of the patient.

Discussion: Our results will have an implication on the use of the quadriceps sparing approach, as they highlight another possible limitation of this approach. Patients need to be warned before the TKA that the quadriceps sparing approach may not be possible in all, especially if they are younger.

Hallux Valgus (HV) surgery is the most common surgery performed in the foot. The Cochrane review done in 2004 showed that no osteotomy is superior to another, however, surgery was shown to be superior to conservative or no treatment for Hallux Valgus deformity. We performed a postal survey in August 2005, to determine the most common procedures performed for HV deformity, type of anaesthesia used, and the length of stay for Hallux Valgus surgery across the United Kingdom.

A list of foot and ankle surgeons was obtained from the BOFAS register and a questionnaire was sent. We received 122 (61%) responses from 200 questionnaires sent. Out of which 4 had retired and 118 were available for analysis.

The table below demonstrates the common procedures performed by those who replied. Eight-eight percent of the surgeons used foot block along with GA, 9% used GA only and 3% performed the surgery under regional anaesthesia only. Forty percent of surgeons performed the surgery on an overnight stay basis and 30% performed the surgery as a day case. Twenty-five percent of surgeons mentioned that they performed unilateral surgery as a day case and bilateral surgery on an overnight stay basis. Less than 5% kept the patients for more than 2 days.

From the responses, most surgeons in the United Kingdom perform Scarf osteotomy with or without Akin osteotomy for Hallux Valgus correction. The majority performed it on an overnight stay basis or as a day case. Most commonly, foot block along with NSAID’s were used for post-operative pain relief.

We reviewed the clinical and radiological outcome of 72 Co-ordinate prostheses (DePuy, Warsaw, Ind) used for revision knee arthroplasty performed by a single surgeon from May 1994 to December 1997. Twenty-three patients (25 knees) since died. Two were lost to follow-up. At a mean follow-up of 10 years (range 9–12years), 45 knees in 43 patients were available for review. There were 12 men and 31 women with a mean age of 71.34 years (range 43 to 87 years). The reason for revision was instability in 38 knees, infection in 5 knees and stiffness in 2 knees.

There was a significant improvement in the SF-12 PCS and WOMAC pain and stiffness scores at the latest follow-up. Five of these knees had to have re-revision surgery. One patient had a re-revision for aseptic loosening, one patient for recurrent dislocation of patella. Three patients underwent repeat procedures for infection.

Radiological evaluation using the Knee Society system revealed well-fixed components in 35 knees (77.78%). The radiolucencies of varying degrees were present in 10 knees (22.22%). Eight had non-progressive radiolu-cencies and did not show any evidence of loosening. 25 (55.5%) knees had halo sign (radiopaque line) present around the prosthesis (7 were femoral side, 4 were tibial side and 14 around both the prosthesis). Using Kaplan Meier method the cumulative survival rate was 88.87% at 12 years, removal of the prosthesis or re-revision were used as end points. An analysis of clinical and standard radiographic outcomes has revealed that the Co-ordinate revision knee system continues to function satisfactorily at a mean of 10 years.

The use of effective pre-operative preparation solution is an important step in limiting surgical wound contamination and preventing infection, particularly in forefoot surgery. The most effective way is unknown. In recent studies, > 70% of aerobic bacterial cultures of specimens taken from the nail folds following skin preparation with povidine iodine were positive. The aim of the study was to determine the effectiveness of pre-operative Triclosan (Aquasept) shower, skin preparation using povidone iodine and ethyl alcohol in reducing post-operative forefoot infection.

Between February 2005 and August 2005, all patients undergoing forefoot surgery under the care of the senior author were followed prospectively. There were 50 women and 10 men with an average age of 55 years (17–92 years), who underwent 92 forefoot procedures. The surgeries included 35 (38%) osteotomies, 31 (34%) arthrodeses, and 9 (10%) Morton’s neuroma excisions and 17 (18%) soft tissue procedures. As a standard protocol, pre-operatively all patients had Triclosan shower on the day of surgery, the foot/feet were painted with povidone iodine and was covered with a sterile towel in the ward. At induction, everyone received cefuroxime 1.5gm (IV); the feet were prepared using povidone iodine and then ethyl alcohol and dried. Patients were followed up in the clinic at 2weeks, 6weeks and 3months, further follow-up if necessary.

None of the patients in the study developed deep infection. Two patients required oral antibiotics for superficial infection (one pin track infection after distal inter-phalangeal joint fusion of second toe, one following scarf osteotomy)

We conclude that the method used in this study was very effective in preventing infection following forefoot surgery.

To assess the outcome and implant removal rate following surgical stabilisation of patella fracture.

Sixty-seven patients who underwent surgical stabilisation of patella fracture between January 1999 and December 2004 were retrospectively reviewed to determine the adequacy of fracture stabilisation, fracture union and implant removal rate.

Forty-three were men and 24 were women with a mean age of 49 years (ranged 14–90 years). Table below demonstrates the injury, fracture patterns and fixation methods. There were 3 open fractures and associated injuries were noted in 22 patients. All fractures united even though the fixation was inadequate in 46 patients. Two superficial infections responded to oral antibiotics. One patient had revision surgery at 6 weeks. Twenty-two patients required implant removal between 2 and 20 months (average 11 months) for implant related symptoms. Of the 22 (32.8%) patients requiring implant removal, 16/40 (40%) were less than 60 years and 6/27 (22.2%) were over 60 years. Mean follow up in asymptomatic patients was 8 months (3 to 18 months) and in patients with implant related problems was 17 months (10 to 36 months). Four patients were lost to follow up.

Surgical stabilisation by current techniques demonstrated satisfactory fracture union. However, one in three required second surgery for implant related symptoms. In the under 60 years group, the implant removal rate increased to 40%. Newer techniques to avoid skin irritation need to be considered.

Background and objectives: Total knee replacement (TKR) produces severe postoperative pain. Peripheral nerve blocks can be used as analgesic adjuncts for TKR, but the efficacy of a sciatic nerve block as an adjunct to a femoral nerve block is controversial. The aim of this study was to compare femoral with femoral and sciatic nerve blocks in postoperative pain management of patients undergoing total knee arthroplasty (TKA).

Methods: 42 patients were involved in the study. 20 patients received only a femoral nerve block, consisting of 20ml of 0.5% Chirocaine and 22 patients received femoral and sciatic nerve blocks, consisting of 20ml of 0.375% Chirocaine for the femoral nerve and 10ml of 0.5% Chirocaine for the sciatic nerve. The primary outcome measures used were visual analogue scale (VAS) scores for pain at 24 hours, 48 hours and 72 hours after the surgery, opiates consumption post-operatively and PCA use. The secondary outcomes were post-operative nausea and vomiting, sensory deficit, quadriceps contraction, straight leg raise, knee flexion, independent mobility and discharge from the hospital.

Results: The results showed no difference in opiate consumption, PCA use, independent mobility and time of discharge from the hospital between the two groups.

Conclusion: The study shows that the addition of a sciatic nerve block to the femoral nerve block does not provide additional benefits.

Objective: To assess functional outcome and complications in patients with Weber C fracture following syndysmotic screw removed.

Patients & Methods: Forty three consecutive patients with closed Weber C type ankle fractures between 2002–20003 were studied. The syndysmotic screw was removed at 6–12 weeks time post operatively. Postoperative complications and functional outcome were studied.

Results: Following removal of the syndysmotic screw 6 patients had superficial wound infection, 4 patients had pain due to instability, one patient had DVT and one patient had broken screw. The functional outcome using ankle scores compared to the other studies in the literature did not show any significant difference.

Conclusion: Syndysmotic screw removal has significant morbidity. Guidelines with randomised control studies are recommended.

The aim of this study was to evaluate whether using a predetermined entry point and standard value for valgus cut could restore normal mechanical axis of the TKA.

The study included 125 consecutive patients, who underwent TKA under care of the senior author (NJD). Details of height, weight, BMI were noted. All the radiographs were taken with the patient standing, with the knees in maximum extension, with the patella facing forward. The long leg radiographs were evaluated and the mechanical axis and anatomical axis were marked. The entry point (EP) and the angle between the anatomical and the mechanical axis of the femur ware measured, which is valgus angle of distal femoral cut (VA). Statistical analysis was done using SPSS (Table 1). Proportion of the cases with VA less than 6 degrees or more than 7 degrees were identified. Similarly cases with EP distance less than 0 and more than 5mms were also identified. Cases with VA of 6–7 degrees and EP 0–5mms were identified as one group. Correlation was performed using nonparametric tests.

The results revealed the angle between the anatomical and the mechanical axis ranges from 4 to 9.5 degrees (mean 6.8 degree and standard deviation 1.11 degree). Only 53% had an angle of between 6 and 7 degrees, with 7% of knees having an angle of less than 5 degree or greater than 8 degrees.

The site of entry of the jig showed variation from 30mms medial to the centre to 18mms lateral to the centre with the mean entry point of 5.04mms medial to centre of the notch, with a standard deviation of 8.5mms.

Overall only 33% of the knees templated would have an optimal femoral jig placement and distal femoral angle cut with an entry point in the centre of the notch or up to 5mms medial to centre and a distal valgus cut of between 6 and 7 degrees. The author feel this study gives evidence that if the mechanical axis is to be restored then long leg pre-operative radiographs should be performed and used as a key component to the pre-operative plan.

Table 1. Spearman’s rho correlations, between the valgus angle and entry point to the height, weight and BMI of the patients.

Stem dissociation in modular revision knee replacement due to failure of the frictional lock of the Morse taper has been reported in the literature. However, the medium and long-term implications of stem dissociation are unknown, as clinical outcomes have not been reported. We report a series of 10 cases in which there was intra-operative dissociation of the tibial stem.

Between 1994 and 1999, 98 patients underwent revision total knee replacement for aseptic loosening at our institution. Ten of these patients were noted to have tibial stem dissociation, apparent on the immediate post-operative radiographs. The senior author (RWP) performed all procedures and used a standardized operative technique. The Co-ordinate modular knee revision system was used in all cases. The quality of the bone was noted in all the cases intra-operatively; and was graded as 1) sound bone, 2) soft but intact, 3) soft and fractured cortex.

Our study demonstrates that the tibial stem dissociation did not cause any significant detriment to the clinical outcome on minimum follow-up of six years in nine cases where the tibial metaphyseal cortical rim was intact. In one case, where the medial tibial plateau had a cortical defect, the prosthesis drifted into varus mal-alignment and the patient required a further revision for aseptic loosening. We therefore question whether long canal filling tibial stems are necessary in all revision total knee replacements particularly when the cortical rim is intact and a non-constrained poly-ethylene insert is used.

The emergence of minimally-invasive total knee replacement (TKR) has led to the refinement of several surgical approaches, including the quadriceps-sparing and sub-vastus. There is some disagreement as to the precise definition of the term ‘minimally-invasive’, especially in regard to the preservation of vastus medialis obliquus (VMO). It is known that the termination of VMO is variable and may make these approaches difficult. We have attempted to assess the factors influencing the insertion of VMO and the impact which they have on the approach for TKR.

The MR scans of 198 knees were examined to assess the variation in the insertion of VMO in relation to the patella and the effect of variables such as age, gender and the presence of concurrent osteoarthritis of the knee on the insertion.

Our findings showed that both age and the presence of osteoarthritis were contributing factors to changes in the level of insertion of VMO. Therefore, not all capsular incisions which extend proximal to the midpole of the patella will violate the quadriceps tendon.