Introduction

Classical fixation using a circular frame involves two rings per segment and in many units this remains the norm whether using ilizarov or hexapod type frames. We present the results of two ring circular frame at King's College Hospital.

Introduction

Patients undergoing complex limb reconstruction are often under immense physical, psychological and financial stress. We already provide psychological support within our unit. We have identified that patients struggle to obtain proper advice on the financial support to which they are entitled. In September 2019, rebuildcharity.org commissioned a Citizens Advice Clinic. One advisor from the local Citizens Advice staffs the clinic. Currently we have no set criteria for referral and patients can be referred by any member of the limb reconstruction team. Although severely affected by the coronavirus pandemic and the disruption of all routine work we were able to run clinics from September 2019 to March 2020 and September 2020 to January 2021. We present our initial results.

The locked plates are commonly used to obtain fixation in periarticular and comminuted fractures. Their use has also gained popularity in fixing fractures in osteoporotic skeleton. These plates provide stable fixation and promote biological healing. We have used over 150 locked plates with varying success in last 3 years to fix periarticular fractures involving mainly Knee and Ankle. These plates need to be removed if indicated which may be implant failure, infection, non-union or a palpable symptomatic implant. There are no reports in the literature regarding complications associated with removal of these locked plates. We report our clinical experience of removing locked plates in 28 adult patients. The procedure of implant removal was associated with a complication rate of 25%. The main problems encountered were difficulty in removing the locked screws and the implant itself. The locking plate could not be removed in two patients and had to be left in situ. We recommend that surgeon should be aware of these potential complications whilst removing these plates and that fluoroscopic control and all available extra equipment mainly metal cutting burrs and screw removal set should be available in theatre.

Aim: Accurate soft tissue balance in total knee arthroplasty (TKA) is not only technically challenging but also difficult to teach to trainees; we believe that computer navigation provides a very useful tool for objective and reproducible soft tissue balance.

Methods: We studied 52 patients (31 females and 21 males) with knee osteoarthritis and recorded the change of the Medial (MCL) and Lateral Collateral Ligament (LCL) length at full extension and at 90o flexion. Pre- and post-operative results were compared. The assessment was performed by consultant orthopaedic surgeons using trackers and navigation knee replacement software. Data was analysed using the student t-test

Results: The navigation software programme was used to measure the change of the collateral ligament length. Ligament laxity is represented by a negative number and a positive number is used to represent stretching and apparent elongation of the ligament.

The medial collateral (MCL) length at full extension ranged from −9mm to 11mm and post-operatively was reduced to −16mm and 8mm, (p=0.042). At 90o flexion the length ranged from −3mm to 9mm and postoperatively was reduced to −8mm and 10mm (p=0.025).

The lateral collateral (LCL) length at full extension changed from −10mm to 9mm pre-operatively to −13mm and 6mm post-operatively (p=0.011). At 90o flexion the range from −8mm and 9mm pre-operatively changed to − 5mm and 11mm post-operatively (p=0.005).

All the above changes correspond to improvement in the post-operative axial alignment.

Conclusion: Our results demonstrate that computer navigation provides a useful adjunct to the accurate and reproducible soft tissue balance in knee arthroplasty which can be used to evaluate results and for training purposes.

Aims: Kinematics of the arthritic knee joint is to date not very well understood, yet this is a significant parameter affecting the results of knee arthroplasties; we studied the axial rotation of the tibia during knee flexion in osteoarthritic knees in order to understand better the kinematics of the arthritic joint.

Methods: Tibial rotation and the screw home mechanism were studied in 55 consecutive patients (31 females and 24 males) with diagnosed knee OA. The assessment was performed by consultant orthopaedic surgeons using the trackers and the software of a navigation system, prior to any soft tissue release. The Student t-test was used for the statistical analysis.

Results: We identified 3 different patterns of tibial rotation during knee flexion.

26 knees had normal tibial rotation pattern with the tibia rotating internally during knee flexion (mean rotation: 15.5°).

We also recorded that most of the tibial rotation occurs in the first 0–30° of flexion (70%) p< 0.001.

Conclusion: The screw home mechanism and the normal tibial rotation upon knee flexion were absent or distorted in the majority of osteoarthritic knees. We found three distinctive patterns of the tibial rotation (normal, erratic and reversed) during knee flexion.

Proximal humeral fractures are common injuries but there is no general agreement on the best method for fixing unstable and displaced 3 & 4 part fractures. A new implant – Proximal Humeral Internal Locking System (PHILOS) – has recently been introduced to fix these fractures. The aim of this study was to assess the effectiveness of the PHILOS plate in the surgical treatment of these fractures.

We operated upon 36 patients between March 2002 and December 2004. 33 of them were available for follow up, which ranged from 12–45 months. Assessment at follow up included radiological review, Constant and DASH scoring.

While recovery of movements and relief in pain was satisfactory, the strength of shoulder did not recover fully in any patient. There were two failures in our series, one due to breakage of plate. 4 patients have shown radiological signs of avascular necrosis of humeral head. The plate was removed in 4 patients due to impingement and / or mechanical block in abduction. Another 2 patients had to undergo arthroscopic subacromial decompression for the same reasons. We encountered the problem of cold welding and distortion of screw heads, while removing the PHILOS plate.

The broken plate was subjected to biomechanical and metallurgical analysis, which revealed that the plate is inherently weak at the site of failure.

The PHILOS plate does have inherent advantages over other implants for fixation of 3 and 4 part proximal humeral fractures but we are not convinced about its strength. Design of its proximal screws also appears less than satisfactory. The plate may cause impingement in some patients necessitating its removal later on, which itself may not be easy.

The movement of a normal knee is a complex of flex-ion-extension, translation and rotational movements. Intracapsular anatomical structures such as ACL, PCL, menisci, the bone anatomy as well as the muscles acting on the knee joint influence the screw home mechanism.

We assessed the axial rotation of the tibia during knee flexion in order to better understand the kinematic behavior of osteoarthritic knees.

We included 55 consecutive admissions (31 females and 24 males) with diagnosed osteoarthritis of the knee. All records were obtained by consultant orthopaedic surgeons using the trackers and software of a navigation knee replacement system, prior to a knee replacement surgery. All the records were obtained before any soft tissue release.

For the statistical analysis we used the Wilcoxon non parametric two sample test.

We found that the tibial rotation on knee flexion followed three distinct patterns: a) normal rotation: 26 knees (47%) with average rotation of 15.96° (range: 0.5°–34°). b) mixed internal and external rotation: 22 knees (40%) with average rotation 6.7° (range: 5°–0.5°) ^and c) reversed rotation: seven knees (13%) with average external rotation of 2.7^{° (}range:1°–4°).

Most of the tibial rotation occurs in the first 0–30° of flexion (70%) p< 0.001.

Our study confirms that osteoarthritis affects the normal kinematics of the knee joint and also suggests that the observed kinematics follow distinctive patterns.

We studied the change in the axial rotation of the tibia at different levels of knee flexion after Knee Replacement using navigation systems.

We reviewed the knee kinematic data of 36 consecutive patients (15 males and 21 females) who underwent elective knee replacement (Scorpio/Stryker) at King’s College Hospital. All data were generated using the navigation TKR trackers and software of a knee replacement system. All preoperative data obtained before any soft tissue release. We studied the tibial rotation at 30°, 60° and 90° of knee flexion. All operations were performed by consultant orthopaedic surgeons. We used the Wilcoxon non parametric two sample test for statistical analysis.

The average tibial internal rotation upon knee flexion was 9.4° preoperatively and was reduced to 5.3° (mean 7.3°) post operatively. Most of the change (80%) occurred within the first 30° of flexion (p< 0.001). Postoperatively 38% of the studied knees had the screw home mechanism preserved. 52.7% had a mixed pattern of both internal and external rotation of the tibia and three knees (8%) had a reversed rotation of the tibia. The abnormal screw home pattern was preserved in 16 of the postoperative joints (46%). One knee was found postoperatively with external tibial rotation in all flexion increments. The abnormal pattern of tibial rotation was not improved following a navigation arthroplasty.

We found that computer navigated TKR reduces significantly the tibial rotation and the replaced knee joint does not behave as a hinge joint. Pre-existing abnormal tibial rotation patterns were not improved postoperatively.

Introduction: It is unknown what effect distraction osteogenesis has on bone blood flow to the affected limb. Our study analyzed in vivo measurement of tibial blood flow during distraction osteogenesis using Doppler ultrasonography.

Materials and Methods: Blood flow was measured in the femoral artery, with Doppler ultrasonography in five people treated with bi-focal tibial distraction osteogenesis. The normal leg was used as the control to correct for differences in cardiac output. Measurements for each leg were taken and means recorded preoperatively, at 1 week postoperatively, and at subsequent intervals up to 6 months.

Results: Preoperative blood flow varied from 0.5 – 2.25. All treated legs demonstrated increases in flow from 2.25 – 5.75, with peaks in the first weeks following osteotomy. Significant increases in blood flow during treatment with distraction osteogenesis, confirming previous experimental studies.

Discussion: Blood flow plays a significant role in the successful outcome of this treatment. Compression of the non-union at the time of peak blood flow gives more reliable union than bone transport methods, where docking takes place when blood flow has returned towards the control limb.