Introduction: Weber B fractures are one of the most common fractures of the ankle. Unstable fractures are treated with lateral plating and a lag screw. Another method of fixation is antiglide plating, this concept was first introduced by Brunner and Weber in 1982.

Manoli and Schaeffer in 1987, showed that fixation by antiglide plate demonstrated superior static biomechanical properties compared to lateral plating.

However there are some shortcomings in their study and hence we decided to perform our biomechanical study. The shortcomings of the Manoli study are. They did not use an interfragmentary lag screw for lateral plate fixation. It was a cadaveric study where the bone does not accurately represent the live bone. The quality of the bone ranging from normal to osteoporotic bone varies from cadaver to cadaver and hence there is no uniformity between the samples.

Materials and Methods: We used 4th generation composite bone models validated to closely simulate human bone characteristics for fracture toughness, tensile strength, compressive strength, fatigue crack resistance and implant subsidence. 4th generation composite bone model provides uniformity of test samples which is not achievable in cadaveric studies.

These bones were custom made for the experiment. We used two sets of bones, one representative of normal bone (Set A n=10) and the other of osteoporotic bone quality (Set B n=10). Each of the sets A & B will have two types of fixations for artificially created Weber B Fractures.

Lateral plate with interfragmentary lag screw.

The strength of the fixation was measured by restressing the bone until the fixation failed using an Instron machine which simultaneously applied torque and compressive forces to the fibular construct. The resulting data was analysed on a computer and statistical analysis was performed.

Results: When the two fixation constructs were stressed to failure, the lateral plate construct demonstrated less stiffness (3–5Nm/degree) and failed at lower energy levels (250Nm). Similar values obtained for the antiglide system were, stiffness of 12–16Nm/degree and energy absorbed to failure 350–450Nm. Antiglide plating was significantly more stable in the osteoporotic fibula.

Conclusion: Antiglide plating with lag screw is much more stable than lateral plating. It is suitable for treatment without plaster cast post operatively. It results in a more stable fixation in osteoporotic bone.

Introduction: Traditionally the fixation of choice as recommended by the AO ASIF group for transverse fractures of the Olecranon and the Patella is the tension band wiring technique.

The concept of tension band wiring is based on the fact that the distractive force applied to one surface of the bone will result in compression on the opposite articular surface.

Clinical outcomes of TBW are not equivocal. It is associated with significant morbidity such as non union, failure of fixation, especially in osteoporotic bone and infection which sometimes leads to amputation. Often a second procedure for removal of prominent metal work is required.

In our biomechanical study we investigated this concept as we believe that the forces generated by TBW construct do not generate significant compressive forces required for healing of fracture.

Materials and Methods: We used 4th generation composite bones (Sawbones^®, Malmoe, Sweden.). These bone analogues have been validated to closely simulate human bone characteristics for fracture toughness, tensile strength, compressive strength, fatigue crack resistance and implant subsidence.

The advantage of using 4th generation composite bone model is that it provides uniformity which is not achievable in cadaveric studies. Two different bone models representative of Olecranon and patella were used. Transverse fractures were created in the bones and fixed with TBW technique as described in A.O. manual.

Two 0.062-inch Kirschner wires and figure of eight configuration of 18G Stainless steel wire with single knot technique was used. Micro motion transducers (DVRT: MicroStrain, Williston, Vermont) with an accuracy of ± 1μm were placed across the fracture site both anteriorly and posteriorly. Continuous information regarding fracture distraction and compression, as determined by the transducers was recorded from both sites simultaneously during the experiment.

The tension band wire construct was loaded up to a maximum force of 4000 Newtons for patella and 500 for the olecranon. The fractures were subjected to cyclic loading at 1Hz using a servo hydraulic materials-testing system (model 8500; Instron, Canton, Massachusetts). The results were analysed on a computer and statistical analysis performed.

Results: During the application of cyclical loading, we noted a gap at the articular surface ranging from 1.1± 0.4mm and 2.1± 0.6mm for Olecranon and patella constructs respectively. During most of the duration of the experiment no transducer displacements were recorded at the articular surface.

Conclusion: The concept that distractive forces at one end could be converted to compression at the other end through the TBW does not hold true in our biomechanical study. A simpler construct may suffice for fixation of patellar and Olecranon fractures which can reduce the complications associated with TBW fixation.

Introduction: In clinical practice The Cascade sign is widely used to assess the rotational deformity of the fingers associated with metacarpal and phalangeal fractures. We carried out a scientific study on thirty volunteers to evaluate the validity or otherwise of this standard sign.

Material and Methods: Metal pointers were attached to the dorsum of the fingers, flexed at MCP and PIP joints. These pointers represented the mid longitudinal axis of the phalanges. Standardised AP radiographs of the closed fist were taken in all cases with the wrist placed in neutral position, in a custom made jig. The radiographs were assessed by two different observers using Picture Archiving and Communication System, software version VA42B, to determine the convergence of the metal pointers towards the scaphoid tubercle, as described in the cascade sign and Lister method..

Statistics: Power of the study was determined with an assumption of a type-2 error of 0.05 and a two sided test. Descriptive statistics and confidence limits were calculated using SPSS 11 software.

Results: We observed that the metal pointers did not equivocally converge towards the scaphoid tubercle. The persistent pattern of convergence was within a 2–3cm radius of the scaphoid tubercle. The statistical analysis, two tailed paired t-test of this pattern showed strong association with this latter finding. (p< 0.003).

Conclusion: Our study suggests that the cascade sign is sensitive but not specific to access the rotational deformity of the fingers. Radiological there is significant scatter about the scaphoid tubercle.

Background/Aim: A preliminary biomechanical study conducted on cadaver fibulae, was observed to have a significant (p< 0.001) difference between two different methods of interfragmentary screw fixation for oblique fractures.

A further study was undertaken to verify the results on composite material with biomechanical properties similar to human bone.

Material and Methods: Forty, custom designed composite fibular specimens were used for the biomechanical testing. The specimens were divided into two groups of 20 each. Group I comprised of specimens with biomechanical properties similar to young healthy bone and group II comprised of osteoporotic bone quality. The fibular specimens were osteotomised to resemble a short oblique fracture of the lateral malleolus. The fractures were fixed with interfragmentary cortical lag screws placed in antero-posterior and postero anterior directions, 10 samples in each group.

Results: In both groups, the mean force required to disrupt the fracture fixation was observed to be 0.45 kN higher in samples fixed with screws placed in postero anterior direction.

Conclusion: This study further confirms the screw placement in postero- anterior direction provides a stronger biomechanical construct for short oblique fracture of the lateral malleolus.

Purpose: Trapezium excision and arthroplasty combined with ligament reconstruction as a treatment for first carpometacarpal joint arthritis is known to be associated with synovitis, prosthesis subluxation /dislocation and proximal migration of the metacarpal. To determine the effectiveness of our technique we used the objective and subjective outcome scores to assess the long term results

Methods: Ten patients (11 thumbs) underwent trapezium arthroplasty and ligament reconstruction procedure for grade III/ IV Eaton and Glickel arthritis. The FCR tendon was harvested split into half from proximal to its insertion site. The insertion site was left intact, the split tendon was passed through the first metacarpal base, passed along the radial side of the implant, through scaphoid and back to the 1st metacarpal as an entrapment technique. 7 female and 3 male patients with mean age of 53.9 comprised our series. Off the 10 patients 60% had surgery on their dominant hands.

Results: All the patients had excellent results at a mean follow up of 33.5 months. The mean score (Buck-Gramco) for the tip pinch, grip strength and subjective score for pain, function and dexterity was comparable to the contra-lateral side. The mean tarpezial space ratio calculated from plain x-rays at the follow up was 0.37cm (p< 0.01)|There was evidence of synovitis, prosthesis subluxation or shortening of the thumb.

Conclusions: This new method of securing the prosthesis does offer excellent results with good patient satisfaction

A study on cadaver ankles was performed; two methods of ‘Danis-Weber type B’ lateral malleolar fracture fixation were compared.

Materials and Method: Ten ankles from five female cadavers were used. The distal fibulae were osteotomised at the level of the syndesmosis with a saw and the fracture fixations were divided into two groups. In Group I, the fractures were fixed with traditional anteroposterior cortical screws and in Group II, the contra lateral fractures from the same cadaver were fixed with postero-anterior cortical screws. The distal fibulae in both groups were subjected to biomechanical compression and torsion forces and the force at which the fixation gave way was recorded.

Results: In the former group the breaking force was significantly lower than that required in the latter group by a mean of 0.4 kN.

In conclusion, the fixation done in Group II was found to be better.

Aims: Treatment options for proximal humeral fractures are not very clear, specially in osteoporotic bones. Non operative treatment if on one hand leads to unpredicted and poor outcomes, the operative treatment on the other hand leads to devascularization of fractured fragments and implant failure leading to unacceptable results. Newer interlocking plates, which are applied with minimum soft tissue stripping of fractured fragments and better fixation abilities seems a promising alternative. We present our experience with such plates.

Patients and Methods: Over a period of two years 2002 and 2003, we used 50 plates to treat Neer’s two and three parts and surgical neck of humerus fractures. We reviewed our clinical results with PHILOS plates, which is in interlocking plate. Average age was 34 (24–82). 21 Male and 29 Females. We followed them clinically and radiologically for healing. The shoulder function was assesses with DASH scoring system. The DASH system questionnaire was filled by patients before the fracture and after healing of the fractures. We used a regimen of progressive rehabilitation of shoulder from immediate post operative period. All the complications including union issues, shoulder function, wound problems, nerve injuries, infection and implant failure were noted. Two different techniques were used to fix the fracture with the plate.

Statistical analysis was performed on the data collected through DASH questionnaires along with multivariate and univariate analysis and t-tests.

Results: We were able to follow all the patients who filled the pre fracture and post healing DASH system questioner. X-rays and clinical findings were available for all the patients in the study. All the patients united with average length of 6 weeks (5–12 weeks). All the fractures united. There were no deep infections; however, two patients had to have a week of oral antibiotics for superficial wound infection. There were no permanent nerve injuries. Eight patients had transient axillary nerve paresis, which resolved after 10–15 days. Patient satisfaction with the procedure was high.

48 % of patients showed a rise in DASH scores after the fracture healing, indicating decrease shoulder function. This was statistically analysed and failed to reach any significance p=0.867. There was no difference between the two techniques in terms of complications and union rates.

Conclusions: PHILOS interlocking plates in our study showed 100% union rate with no or minimal complications and preservation of shoulder function. They are technically not difficult to apply and allow immediate post operative mobilization. Hence we recommend their use in primary fixation of proximal humerus fractures.

Abstract: A study on cadaver ankles was performed; two methods of ‘Danis-Weber type B’ lateral malleolar fracture fixation were compared.

Materials and Method: Ten ankles from five female cadavers were used. The distal fibulae were osteotomised at the level of the syndesmosis with a saw and the fracture fixations were divided into two groups. In Group I, the fractures were fixed with traditional antero-posterior cortical screws and in Group II, the contra lateral fractures from the same cadaver were fixed with postero-anterior cortical screws. The distal fibulae in both groups were subjected to biomechanical compression and torsion forces and the force at which the fixation gave way was recorded.

Results: In the former group the breaking force was significantly lower than that required in the latter group by a mean of 0.4 kN.

In conclusion, the fixation done in Group II was found to be biomechanically more stable.

We retrospectively reviewed medical records and radiographs of 82 children who presented within 12 months of their birth, with unilateral dislocated/subluxed hips and required treatment in from of traction, closed/open reduction, pelvic osteotomy and maintenance. The purpose of the study was to assess if HE angle could be utilized as a prognostic indicator fro assessing reduction of the affected hip. Hilgenreiner epiphyseal angle was measured by two observers for the normal as well as the abnormal side and differences noted. The measurements of the primary presentation and follow-up films were then correlated. Two groups of patients emerged, those in who the difference between the normal and abnormal hips was less than 10 degrees and those in whom was greater than or equal to 10 degrees, on initial presentation. Their management transpired to be quite different (p=0.000), with open reduction/pelvic osteotomy being required in all cases in the latter group.