Aim: We conducted a prospective, randomised study of 50 patients, 40 (80%) male and 10 (20%) female, with anterior cruciate ligament (ACL) rupture to compare the results of ligament reconstruction by middle third patellar tendon graft (M) or synthetic Leeds-Keio (LK) ligament.

Method: The patients were randomised into two groups. 26 (52%) underwent PTG repair and 24 (48%) LK repair. Subjective knee function was classified using the Lysholm score, Tegner activity score and IKDC grading. Laxity was tested by clinical examination including anterior draw, pivot shift and arthrometric measurements using the Stryker Laxometer (Stryker Corporation, Kalamazoo, Michigan, USA).

Results: We present the early (two to five-year follow-up) results of this on-going trial. There was no statistical difference between the two groups in activity levels, both pre-injury and current. However, both pivot shift and anterior laxity were significantly greater in the LK group at two years and greater.

Discussion: While the LK group did develop significantly greater laxity, it is demonstrated that the functional outcome is not affected. We conclude therefore that if the results of surgery were to be based on a functional outcome rather than objective measurements of laxity, it would seem logical that the LK is an acceptable alternative to autogenous PTG.

However whilst function appears to be as good the less successful objective criteria do suggest reservations for the long term results of the Leeds-keio graft.

Objective: To measure intradiscal pressures in scoliotic spines to further understand the role of mechanical forces in the development of scoliosis.

Design: Pressure readings were obtained in consented patients with ethical approval. A needle mounted pressure transducer was introduced into the disc during routine anterior scoliosis surgery.

Subjects: Ten human scoliotic discs from three patients.

Outcome measures: Intradiscal pressure profiles.

Results: Nuclear hydrostatic pressures varied from 0.2 to 0.6 MPa. The mean nuclear pressures for the three spines were 0.27+0.12, 0.35+0.06 and 0.47+0.12 MPa.

High stress, non- hydrostatic regions were consistently recorded in the concave annulus.

Conclusions: Nuclear pressures in these scoliotic patients were significantly higher than the 0.12 and 0.15 MPa recorded previously in non-scoliotic recumbent individuals^1;2 suggesting that spinal loading is abnormal in scoliosis.

Introduction: The progress of post tubeculous kyphosis in children during ‘growth spurt’ is unpredictable and has not been clearly documented in literature.

Methods: The progression of deformity in 63 children treated conservatively and belonging to a controlled clinical trial was studied over 15 years.

Results: The average Kyphosis increased from 35.2 degrees to 41.3 degrees in the ‘Active Stage’ (Phase I), there was an increase in all patients. In the ‘Healed stage’ (Phase II), a variable progress continued which was more prominent during the ‘growth spurt’. In Type I, there was a worsening which occured either continuously (Type 1a; n=19.30%), or suddently after a gap of few years (Type 1b;n=6.9%). In Type II, an improvement occured either after an initial increase or a plateau (Type IIa; n=18.29%), or continuously after disease cure (Type IIb; n=9.15%). In Type III, the deformity was static (n=11.17%). The average increase in Type Ia was 24.2 degrees, Type IIb was 20;5 degrees, Type Ib was 58.4 degrees; the decrease in Type IIa was 4.9 degrees, Type IIb was 20.5 degrees and the decrease in Type III was 1.7 degrees. Overall, the growth spurt sresulted in an increase in deformity in 25 (39%) children, a decrease in 27 (44%) and no change in 11 (17%).

Conclusion:

Post-tuberculous kyphosis in children is a ‘Dynamic deformity’ which changes till skeletal maturity.

Many factors have been demonstrated to influence the range of knee movement that an individual can achieve.

The purpose of this study was to objectively demonstrate how range of knee movement is affected when the influence of pain is abolished.

Sixty-eight patients with degenerative joint disease presenting for primary total knee arthroplasty were recruited. Using a digital camera, images were taken before and after the induction of anaesthesia with the lower limb in four positions- extension, forced extension, flexion and forced flexion. Camera set up was standard and the range of knee motion was measured from the digital images.

Average arc of motion before anaesthesia was 96° (range, 41°–157°). After induction of anaesthesia, the arc of motion increased to 115° (range, 410–161°). Knee extension improved by an average of 5° (range, 0–15°) and flexion improved by an average of 16° (range, 0–65°).

In conclusion, these results demonstrate that pain has a significant inhibitory effect on the measured range of knee movement before surgical intervention.

Dislocation of the polyethylene-rotating platform is a recognised complication of LCS knee arthroplasty.

We report ten cases of rotating platform dislocation out of 2151 primary total knee arthroplasties (0.5%) performed to date in our unit.

Of the ten cases (3 male: 7 female), six patients had a preoperative valgus deformity, two had a varus deformity and the remaining two patients were in neutral alignment, although the wear was predominantly within the lateral compartment. Two patients also had a previous patellectomy on the side of the platform spinout.

Of the ten cases, six patients were symptomatic as a result of their platform dislocation. The remaining four patients were asymptomatic and mobilising without any difficulty. In these patients, the dislocated platform was diagnosed on x-ray at outpatient review. Time to detection of the platform dislocation ranged from six days to two years.

Three patients required revision of their original insert to a larger, deeper dish insert. Three were managed by open reduction of the original insert. Of the remaining patients, one was managed successfully by closed reduction, one required an arthrodesis and one had the tibial insert cemented to the tibial tray. All patients at latest review have a functional and stable knee joint.

In conclusion, we feel that surgical error was to blame for the majority of our ten cases. Furthermore, we emphasise the importance of producing equal and balanced flexion and extension gaps at the time of knee arthroplasty in order to prevent mobile bearing dislocation. A novel technique for reducing a dislocated rotating platform is also described.

The aim of this trial was to assess the clinical examination findings commonly used for the ACL deficient knee.

For reliability testing and criterion validation 102 patients with ACL injuries were assessed by a single observer, 35 by a second observer and 47 again by the initial observer. For construct and criterion validation 30 patients were assessed pre-operatively and a mean of 1.7 years after ACL reconstruction. The Lysholm 11, Tegner and Cincinnati outcome measures were assessed along with instrumented knee laxity (Stryker test), the one hop test (OHT) and graded tests (including anterior draw, Lachman test, quality of end point, and pivot shift test).

The outcome measures were found to be reliable except the Cincinnati system. All examination findings were of unsatisfactory reliability, with the exception of the OHT and the Stryker test. Construct validation revealed a significant improvement in all outcome measure scores and examination findings following ACL reconstruction. Criterion validation revealed that of the examination findings only the OHT had a satisfactory correlation with the symptom of giving way and the Lysholm/Tegner measures. Comparison of the difference between the desired and actual Tegner activity levels with the examination findings revealed an improvement in all levels of correlation.

With the exception of the OHT, the clinical examination findings used for the ACL deficient knee are unreliable and correlate poorly with the functional outcome of the patient. They may, however, have some benefit in assessment of deficiency of the anatomical structures and the findings should be presented individually, rather than forming part of the functional assessment of the patient.

The aim of this randomised prospective study was to establish whether the use of knee splints following total knee replacement is necessary.

The study included 81 patients undergoing total knee replacement who were randomised into a ‘splint’ and a ‘no splint’ group postoperatively. Patients in the ‘splint’ group had their knee splinted in extension in the early post-operative period but the splint was removed for the patients to do exercise. Splintage was completely removed when the patient could straight leg raise. Patients in the ‘no splint’ group had a wool and crepe bandage applied around their knee and allowed to fully mobilise from the first postoperative day. The following parameters were recorded: The range of movement preoperatively, 5 days post-operatively and 6 weeks postoperatively; the length of time to straight leg raise; the blood drained from the wound. and the amount of postoperative analgesia required.

Using the unpaired 2 tailed t-test it was found that patients in the four ‘no splint’ group achieved significantly greater flexion at 5 days and 6 weeks post-operatively but drained significantly more blood from the wound. Transfusion requirements were similar in the two groups. There was no other significant difference in the parameters measured between the two groups.

In conclusion we found no evidence to advocate the use of knee splints following total knee arthroplasty.

Purpose: Posters of study: To produce a virtual reality model of prosthetic knee joint motion, giving detail regarding contact area and contact pressures during the process of walking.

Method: Using serial CT scans and data regarding the material properties of bone, cartilage, ligaments and other soft tissue structures a computational “virtual reality model” of the knee has been constructed. This computational model which is a 3D dynamic representation of a human knee joint, may be programmed to replicate the standard gait pattern of the human knee.

This study details the development of this model and its validation against the accepted Stenmore Test Rig for modelling of knee joint movement and knee prosthetic wear. The validation results will be presented,

The model allows the calculation and representation of contact pressures and contact areas in the knee joint as it moves through the gait cycle. This study also shows the effect of uni-condular loading and varus mal-positioning which may occur at surgery and the effect this has on the contact area and contact pressures of a prosthetic knee in ambulation. The resultant gait pattern produced by uni-condular loading and exhibited by the virtual knee closely resembles that seen in In Vivo Kinematic Studies reported by other authors.

In conclusion we present this as a valid computational dynamic model of knee prosthetic wear and kinematics which represents an enormous advantage over standard mechanical testing and presents possibilities for rapid analysis in new knee joint designs and the effect of abnormalities of gait and wear.

Two dimensional ultrasound of the shoulder joint has become a well established diagnostic tool. Difficult interpretation of ultrasonographic findings, however, suggests that ultrasound appears not to be an always reliable method, especially in partial thickness tears. The present study was performed to determine whether the use of three dimensional (3D) sonography further increases the diagnostic yield of ultrasound.

On a total of 22 externally intact appearing rotator cuffs of cadaveric shoulder joints 7 full thickness and 15 partial thickness incisions were carried out on the M. supraspinatus, subscapularis and infraspinatus tendon. The specimens included the humeral head, the glenoid, the joint capsule and periarticular tendons.

Ultrasound was performed on the shoulder specimens in a water basin with a 8.5 MHz curved array transducer (Combison 530D, Kretztechnik, Zipf, Austria).

With three dimensional ultrasound rotator cuff lesions were more often correctly diagnosed (sensitivity of 77 %) than with conventional 2D sonography (sensitivity of 64 %). Specificity was 85 % and 69 %, respectively. In partial thickness tears in particular, 3D imaging was the superior method reaching a sensitivity and specifity of 73% and 77%, respectively compared to 53% and 61%, respectively with 2D ultrasound.

The use of three dimensional ultrasound appears to have a higher diagnostic yield in partial thickness tears. One advantage is that the examiner must not move the transducer to obtain other planes. Changes in echogenicity can be observed in the complete volume and in any plane. In the diagnosis of partial tears these changes enabled the examiner to distinguish intact from ruptured tissue.