Aims

The primary aim of this study was to compare the migration of the femoral and tibial components of the cementless rotating platform Attune and Low Contact Stress (LCS) total knee arthroplasty (TKA) designs, two years postoperatively, using radiostereometric analysis (RSA) in order to assess the risk of the development of aseptic loosening. A secondary aim was to compare clinical and patient-reported outcome measures (PROMs) between the designs.

Aims

There are concerns regarding nail/medullary canal mismatch and initial stability after cephalomedullary nailing in unstable pertrochanteric fractures. This study aimed to investigate the effect of an additional anteroposterior blocking screw on fixation stability in unstable pertrochanteric fracture models with a nail/medullary canal mismatch after short cephalomedullary nail (CMN) fixation.

Aims

A lack of supporting clinical studies have been published to determine the ideal length of intramedullary nail in fixation of trochanteric fractures of the hip. Nevertheless, there has been a trend to use shorter intramedullary nails for the internal fixation of trochanteric hip fractures. Our aim was to determine if the length of nail affected the outcome.

Objectives

The paradoxical migration of the femoral neck element (FNE) superomedially against gravity, with respect to the intramedullary component of the cephalomedullary device, is a poorly understood phenomenon increasingly seen in the management of pertrochanteric hip fractures with the intramedullary nail. The aim of this study was to investigate the role of bidirectional loading on the medial migration phenomenon, based on unique wear patterns seen on scanning electron microscopy of retrieved implants suggestive of FNE toggling.

Aims

The aim of this study was to evaluate the outcomes of a salvage procedure using a 95° angled blade plate for failed osteosynthesis of atypical subtrochanteric femoral fractures associated with the long-term use of bisphosphonates. These were compared with those for failed osteosynthesis of subtrochanteric fractures not associated with bisphosphonate treatment.

Objectives

The monitoring of fracture healing is a complex process. Typically, successive radiographs are performed and an emerging calcification of the fracture area is evaluated. The aim of this study was to investigate whether different bone healing patterns can be distinguished using a telemetric instrumented femoral internal plate fixator.

The aim of this study was to quantify the stability of fracture-implant complex in fractures after fixation. A total of 15 patients with an undisplaced fracture of the femoral neck, treated with either a dynamic hip screw or three cannulated hip screws, and 16 patients with an AO31-A2 trochanteric fracture treated with a dynamic hip screw or a Gamma Nail, were included. Radiostereometric analysis was used at six weeks, four months and 12 months post-operatively to evaluate shortening and rotation. Migration could be assessed in ten patients with a fracture of the femoral neck and seven with a trochanteric fracture. By four months post-operatively, a mean shortening of 5.4 mm (-0.04 to 16.1) had occurred in the fracture of the femoral neck group and 5.0 mm (-0.13 to 12.9) in the trochanteric fracture group. A wide range of rotation occurred in both types of fracture. Right-sided trochanteric fractures seem more rotationally stable than left-sided fractures. This prospective study shows that migration at the fracture site occurs continuously during the first four post-operative months, after which stabilisation occurs. This information may allow the early recognition of patients at risk of failure of fixation. Cite this article: Bone Joint J 2015;97-B:391–7

Malpositioning of the trochanteric entry point during the introduction of an intramedullary nail may cause iatrogenic fracture or malreduction. Although the optimal point of insertion in the coronal plane has been well described, positioning in the sagittal plane is poorly defined.

The paired femora from 374 cadavers were placed both in the anatomical position and in internal rotation to neutralise femoral anteversion. A marker was placed at the apparent apex of the greater trochanter, and the lateral and anterior offsets from the axis of the femoral shaft were measured on anteroposterior and lateral photographs. Greater trochanteric morphology and trochanteric overhang were graded.

The mean anterior offset of the apex of the trochanter relative to the axis of the femoral shaft was 5.1 mm (sd 4.0) and 4.6 mm (sd 4.2) for the anatomical and neutralised positions, respectively. The mean lateral offset of the apex was 7.1 mm (sd 4.6) and 6.4 mm (sd 4.6), respectively.

Placement of the entry position at the apex of the greater trochanter in the anteroposterior view does not reliably centre an intramedullary nail in the sagittal plane. Based on our findings, the site of insertion should be about 5 mm posterior to the apex of the trochanter to allow for its anterior offset.

Cite this article: Bone Joint J 2014;96-B:1274–81.

The April 2014 Oncology Roundup³⁶⁰ looks at: Eyeball as good as microscope for tumour margins; when is best to stabilise femoral metastases?; fluorine does not cause bone tumours; whether giant cell tumour of the proximal femur ever successfully managed; extraskeletal osteosarcoma; modular lower limb tumour reconstruction; and observational studies the basis for most bone tumour treatment.

The February 2014 Hip & Pelvis Roundup³⁶⁰ looks at: length of stay; cementless metaphyseal fixation; mortality trends in over 400,000 total hip replacements; antibiotics in hip fracture surgery; blood supply to the femoral head after dislocation; resurfacing and THR in metal-on-metal replacement; diabetes and hip replacement; bone remodelling over two decades following hip replacement; and whether bisphosphonates affect acetabular fixation.

The Gamma nail is frequently used in unstable peri-trochanteric hip fractures. We hypothesised that mechanical failure of the Gamma nail was associated with inadequate proximal three-point fixation. We identified a consecutive series of 299 Gamma nails implanted in 299 patients over a five-year period, 223 of whom fulfilled our inclusion criteria for investigation. The series included 61 men and 162 women with a mean age of 81 years (20 to 101). Their fractures were classified according to the Modified Evans’ classification and the quality of fracture reduction was graded. The technical adequacy of three points of proximal fixation was recorded from intra-operative fluoroscopic images, and technical inadequacy for each point was defined. All patients were followed to final follow-up and mechanical failures were identified. A multivariate statistical analysis was performed, adjusting for confounders. A total of 16 failures (7.2%) were identified. The position of the lag screw relative to the lateral cortex was the most important point of proximal fixation, and when inadequate the failure rate was 25.8% (eight of 31: odds ratio 7.5 (95% confidence interval 2.5 to 22.7), p < 0.001). Mechanical failure of the Gamma nail in peri-trochanteric femoral fractures is rare (< 1%) when three-point proximal fixation is achieved. However, when proximal fixation is inadequate, failure rates increase. The strongest predictor of failure is positioning the lateral end of the lag screw short of the lateral cortex. Adherence to simple technical points minimises the risk of fixation failure in this vulnerable patient group. Cite this article: Bone Joint J 2013;95-B:825–30

Objectives

Because of the contradictory body of evidence related to the potential benefits of helical blades in trochanteric fracture fixation, we studied the effect of bone compaction resulting from the insertion of a proximal femoral nail anti-rotation (PFNA).

In a randomised trial involving 598 patients with 600 trochanteric fractures of the hip, the fractures were treated with either a sliding hip screw (n = 300) or a Targon PF intramedullary nail (n = 300). The mean age of the patients was 82 years (26 to 104). All surviving patients were reviewed at one year with functional outcome assessed by a research nurse blinded to the treatment used. The intramedullary nail was found to have a slightly increased mean operative time (46 minutes (sd 12.3) versus 49 minutes (sd 12.7), p < 0.001) and an increased mean radiological screening time (0.3 minutes (sd 0.2) versus 0.5 minutes (sd 0.3), p <  0.001). Operative difficulties were more common with the intramedullary nail. There was no statistically significant difference between implants for wound healing complications (p = 1), or need for post-operative blood transfusion (p = 1), and medical complications were similarly distributed in both groups. There was a tendency to fewer revisions of fixation or conversion to an arthroplasty in the nail group, although the difference was not statistically significant (nine versus three cases, p = 0.14). The extent of shortening, loss of hip flexion, mortality and degree of residual pain were similar in both groups. The recovery of mobility was superior for those treated with the intramedullary nails (p = 0.01 at one year from injury).

In summary, both implants produced comparable results but there was a tendency to better return of mobility for those treated with the intramedullary nail.

In an interdisciplinary project involving electronic engineers and clinicians, a telemetric system was developed to measure the bending load in a titanium internal femoral fixator. As this was a new device, the main question posed was: what clinically relevant information could be drawn from its application? As a first clinical investigation, 27 patients (24 men, three women) with a mean age of 38.4 years (19 to 66) with femoral nonunions were treated using the system. The mean duration of the nonunion was 15.4 months (5 to 69). The elasticity of the plate-callus system was measured telemetrically until union. Conventional radiographs and a CT scan at 12 weeks were performed routinely, and healing was staged according to the CT scans. All nonunions healed at a mean of 21.5 weeks (13 to 37). Well before any radiological signs of healing could be detected, a substantial decrease in elasticity was recorded. The relative elasticity decreased to 50% at a mean of 7.8 weeks (3.5 to 13) and to 10% at a mean of 19.3 weeks (4.5 to 37). At 12 weeks the mean relative elasticity was 28.1% (0% to 56%). The relative elasticity was significantly different between the different healing stages as determined by the CT scans.

Incorporating load measuring electronics into implants is a promising option for the assessment of bone healing. Future application might lead to a reduction in the need for exposure to ionising radiation to monitor fracture healing.

The results of the treatment of 31 open femoral fractures (29 patients) with significant bone loss in a single trauma unit were reviewed. A protocol of early soft-tissue and bony debridement was followed by skeletal stabilisation using a locked intramedullary nail or a dynamic condylar plate for diaphyseal and metaphyseal fractures respectively. Soft-tissue closure was obtained within 48 hours then followed, if required, by elective bone grafting with or without exchange nailing.

The mean time to union was 51 weeks (20 to 156). The time to union and functional outcome were largely dependent upon the location and extent of the bone loss. It was achieved more rapidly in fractures with wedge defects than in those with segmental bone loss. Fractures with metaphyseal defects healed more rapidly than those of comparable size in the diaphysis. Complications were more common in fractures with greater bone loss, and included stiffness of the knee, malunion and limb-length discrepancy.

Based on our findings, we have produced an algorithm for the treatment of these injuries. We conclude that satisfactory results can be achieved in most femoral fractures with bone loss using initial debridement and skeletal stabilisation to maintain length, with further procedures as required.

Fluoronavigation is an image-guided technology which uses intra-operative fluoroscopic images taken under a real-time tracking system and registration to guide surgical procedures. With the skeleton and the instrument registered, guidance under an optical tracking system is possible, allowing fixation of the fracture and insertion of an implant. This technology helps to minimise exposure to x-rays, providing multiplanar views for monitoring and accurate positioning of implants. It allows real-time interactive quantitative data for decision-making and expands the application of minimally invasive surgery. In orthopaedic trauma its use can be further enhanced by combining newer imaging technologies such as intra-operative three-dimensional fluoroscopy and optical image guidance, new advances in software for fracture reduction, and new tracking mechanisms using electromagnetic technology. The major obstacles for general and wider applications are the inability to track individual fracture fragments, no navigated real-time fracture reduction, and the lack of an objective assessment method for cost-effectiveness.

We believe that its application will go beyond the operating theatre and cover all aspects of patient management, from pre-operative planning to intra-operative guidance and postoperative rehabilitation.

There have been recent reports linking alendronate and a specific pattern of subtrochanteric insufficiency fracture. We performed a retrospective review of all subtrochanteric fractures admitted to our institution between 2001 and 2007. There were 20 patients who met the inclusion criteria, 12 of whom were on long-term alendronate. Alendronate-associated fractures tend to be bilateral (Fisher’s exact test, p = 0.018), have unique radiological features (p < 0.0005), be associated radiologically with a pre-existing ellipsoid thickening of the lateral femoral cortex and are likely to be preceded by prodromal pain. Biomechanical investigations did not suggest overt metabolic bone disease. Only one patient on alendronate had osteoporosis prior to the start of therapy. We used these findings to develop a management protocol to optimise fracture healing. We also advocate careful surveillance in individuals at-risk, and present our experience with screening and prophylactic fixation in selected patients.

An MR scan was performed on all patients who presented to our hospital with a clinical diagnosis of a fracture of the proximal femur, but who had no abnormality on plain radiographs. This was a prospective study of 102 consecutive patients over a ten-year period. There were 98 patients who fulfilled our inclusion criteria, of whom 75 were scanned within 48 hours of admission, with an overall mean time between admission and scanning of 2.4 days (0 to 10). A total of 81 patients (83%) had abnormalities detected on MRI; 23 (23%) required operative management.

The use of MRI led to the early diagnosis and treatment of occult hip pathology. We recommend that incomplete intertrochanteric fractures are managed non-operatively with protected weight-bearing. The study illustrates the high incidence of fractures which are not apparent on plain radiographs, and shows that MRI is useful when diagnosing other pathology such as malignancy, which may not be apparent on plain films.

We compared the outcome of patients treated for an intertrochanteric fracture of the femoral neck with a locked, long intramedullary nail with those treated with a dynamic hip screw (DHS) in a prospective randomised study.

Each patient who presented with an extra-capsular hip fracture was randomised to operative stabilisation with either a long intramedullary Holland nail or a DHS. We treated 92 patients with a Holland nail and 98 with a DHS. Pre-operative variables included the Mini Mental test score, patient mobility, fracture pattern and American Society of Anesthesiologists grading. Peri-operative variables were anaesthetic time, operating time, radiation time and blood loss. Post-operative variables were time to mobilising with a frame, wound infection, time to discharge, time to fracture union, and mortality.

We found no significant difference in the pre-operative variables. The mean anaesthetic and operation times were shorter in the DHS group than in the Holland nail group (29.7 vs 40.4 minutes, p < 0.001; and 40.3 vs 54 minutes, p < 0.001, respectively). There was an increased mean blood loss within the DHS group versus the Holland nail group (160 ml vs 78 ml, respectively, p < 0.001). The mean time to mobilisation with a frame was shorter in the Holland nail group (DHS 4.3 days, Holland nail 3.6 days, p = 0.012). More patients needed a post-operative blood transfusion in the DHS group (23 vs seven, p = 0.003) and the mean radiation time was shorter in this group (DHS 0.9 minutes vs Holland nail 1.56 minutes, p < 0.001). The screw of the DHS cut out in two patients, one of whom underwent revision to a Holland nail. There were no revisions in the Holland nail group. All fractures in both groups were united when followed up after one year.

We conclude that the DHS can be implanted more quickly and with less exposure to radiation than the Holland nail. However, the resultant blood loss and need for transfusion is greater. The Holland nail allows patients to mobilise faster and to a greater extent. We have therefore adopted the Holland nail as our preferred method of treating intertrochanteric fractures of the hip.

We report the case of a 74-year-old woman who sustained an intertrochanteric fracture of the femoral neck in a previously arthrodesed hip. The hip arthrodesis had been performed 53 years earlier to treat septic arthritis. The fracture was treated successfully using a double-plating technique with 4.5 mm titanium reconstruction plates.

We treated 108 patients with a pertrochanteric femoral fracture using either the dynamic hip screw or the proximal femoral nail in this prospective, randomised series. We compared walking ability before fracture, intra-operative variables and return to their residence. Patients treated with the proximal femoral nail (n = 42) had regained their pre-operative walking ability significantly (p = 0.04) more often by the four-month review than those treated with the dynamic hip screw (n = 41). Peri-operative or immediate post-operative measures of outcome did not differ between the groups, with the exception of operation time. The dynamic hip screw allowed a significantly greater compression of the fracture during the four-month follow-up, but consolidation of the fracture was comparable between the two groups. Two major losses of reduction were observed in each group, resulting in a total of four revision operations.

Our results suggest that the use of the proximal femoral nail may allow a faster postoperative restoration of walking ability, when compared with the dynamic hip screw.

We studied 217 patients with an unstable trochanteric or subtrochanteric fracture who had been randomly allocated to treatment by either internal fixation with a standard Gamma nail (SGN) or a Medoff sliding plate (MSP, biaxial dynamisation mode). Their mean age was 84 years (65 to 99) and they were reviewed at four and 12 months after surgery. Assessments of outcome included general complications, technical failures, revision surgery, activities of daily living (ADL), hip function (Charnley score) and the health-related quality of life (HRQOL, EQ-5D). The rate of technical failure in patients with unstable trochanteric fractures was 6.5% (6/93) (including intra-operative femoral fractures) in the SGN group and 5.2% (5/96) in the MSP group. In patients with subtrochanteric fractures, there were no failures in the SGN group (n = 16) and two in the MSP group (n = 12). In the SGN group, there were intra-operative femoral fractures in 2.8% (3/109) and no post-operative fractures. There was a reduced need for revision surgery in the SGN group compared with the MSP group (8.3%; 9/108; p = 0.072). The SGN group also showed a lower incidence of severe general complications (p < 0.05) and a trend towards a lower incidence of wound infections (p = 0.05). There were no differences between the groups regarding the outcome of ADL, hip function or the HRQOL. The reduction in the HRQOL (EQ-5D. index. score) was significant in both groups compared with that before the fracture (p < 0.005). Our findings indicate that the SGN showed good results in both trochanteric and subtrochanteric fractures. The limited number of intra-operative femoral fractures did not influence the outcome or the need for revision surgery. Moreover, the SGN group had a reduced number of serious general complications and wound infections compared with the MSP group. The MSP in the biaxial dynamisation mode had a low rate of failure in trochanteric fractures but an unacceptably high rate when used in the biaxial dynamisation mode in subtrochanteric fractures. The negative influence of an unstable trochanteric or subtrochanteric fracture on the quality of life was significant regardless of the surgical method

The proximal femoral nail (PFN) is a recently introduced intramedullary system, designed to improve treatment of unstable trochanteric fractures of the hip. In a multicentre prospective clinical study, the intra-operative use, complications and outcome of treatment using the PFN (n = 211) were compared with those using the gamma nail (GN) (n = 213). The intra-operative blood loss was lower with the PFN (220 ml v 287 ml, p = 0.001). Post-operatively, more lateral protrusion of the hip screws of the PFN (7.6%) was documented, compared with the gamma nail (1.6%, p = 0.02). Most local complications were related to suboptimal reduction of the fracture and/or positioning of the implant. Functional outcome and consolidation were equal for both implants. Generally, the results of treatment of unstable trochanteric fractures were comparable for the PFN and GN. The pitfalls and complications were similar, and mainly surgeon- or fracture-related, rather than implant-related

The Medoff sliding plate (MSP) is a new device used to treat intertrochanteric and subtrochanteric fractures. There are three options for sliding; either along the shaft or the neck of the femur, or a combination of both. In a prospective series of 108 consecutive displaced intertrochanteric fractures we used combined dynamic compression. The patients were followed clinically and radiologically for one year. All fractures healed during the follow-up period. The only postoperative technical failure was one lag-screw penetration. Combined compression of the MSP gives increased dynamic capacity which reduces the risk of complications. The low rate of technical failure in our series compares favourably with that of the sliding hip screw or the Gamma nail but randomised trials comparing the MSP with other hip screw systems are necessary to find the true role of the MSP with its various sliding modes

To investigate the origin of fractures at the distal locking site of the Gamma nail, we loaded ten paired human cadaver femora fixed with a Gamma nail in torsion until they fractured. When an awl was hammered in to start the hole for distal locking a fissure appeared in the lateral cortex of all the femora, and the mean torsional load to create a fracture was reduced by 57.8% compared with that in a control group in which the distal locking hole had been started with a centre drill. When an additional drill hole was made, the mean failure load in torsion decreased by 35.7%. We strongly recommend that an awl should not be used at the distal locking site of the Gamma nail; we recommend the use of a centre drill. Additional drill holes should be avoided because they act as stress raisers

We made a randomised prospective comparison of the Dynamic Hip Screw and the Gamma locking nail for the internal fixation of 200 petrochanteric femoral fractures in elderly patients. There was less intraoperative blood loss and a lower rate of wound complications in the patients treated by the Gamma nail. They had, however, a high incidence of femoral shaft fracture which we relate in part to implant design. We do not recommend the use of the Gamma nail for these fractures

The Gamma nail was designed to treat unstable intertrochanteric and subtrochanteric fractures. The device was developed after cadaver studies and has been used clinically since February 1985 in a total of 421 patients. The results in 123 patients treated by the third version of this design are reported. The Gamma nail transmits weight closer to the calcar than does the dynamic hip screw and it has greater mechanical strength. A semi-closed operative technique is used, with an average duration of operation of 35 minutes and little blood loss. Distal locking screws can be used to maintain rotational stability, and can be inserted without the use of an image intensifier. Results showed satisfactory fracture union with little loss of position, even in comminuted fractures. Operative complications were few, but included fractures of the base of the greater trochanter. The most important postoperative complication, seen in one case, was fracture of the shaft of the femur at the distal end of the nail, but this healed well after re-nailing

We examined the effect of the Gamma nail on strain distribution in the proximal femur, using ten cadaver femora instrumented with six unidirectional strain gauges along the medial and lateral cortices. The femora were loaded to 1800 N and strains were determined with or without distal interlocking screws before and after experimentally created two-part and four-part fractures. Motion of the sliding screw and the nail was also determined. Strain patterns and screw motion were compared with previously obtained values for a sliding hip screw device (SHS). The Gamma nail was shown to transmit decreasing load to the calcar with decreasing fracture stability, such that virtually no strain on the bone was seen in four-part fractures with the posteromedial fragment removed; increasing compression was noted, however, at the proximal lateral cortex. Conversely, the SHS showed increased calcar compression with decreasing fracture stability. The insertion of distal interlocking screws did not change the pattern of proximal femoral strain. The Gamma nail imparts non-physiological strains to the proximal femur, probably because of its inherent stiffness. These strains may alter bone remodelling and interfere with healing. Distal interlocking screws may not be necessary for stable intertrochanteric fractures

The Gamma nail was introduced for the treatment of peritrochanteric fractures with the theoretical advantage of a load-sharing femoral component which could be implanted by a closed procedure. We report a randomised prospective study of 186 fractures treated by either the Gamma nail or a dynamic hip screw. Gamma nails were implanted with significantly shorter screening times, smaller incisions, and less intraoperative bleeding. The Gamma nail group had a shorter convalescence and earlier full weight-bearing, but there was no significant difference in mortality within six months, postoperative mobility, or hip function at review. More intra-operative complications were recorded in the Gamma nail group, mainly due to the mismatching of the femoral component of the nail to the small femurs of Chinese people. Use of a smaller modified nail reduced these complications. We conclude that with careful surgical technique and the modified femoral component, the Gamma nail is an advance in the treatment of peritrochanteric fractures

We have prospectively compared the fixation of 100 intertrochanteric fractures of the proximal femur in elderly patients with random use of either a Dynamic Hip Screw (DHS) or a new intramedullary device, the Gamma nail. We found no difference in operating time, blood loss, wound complications, stay in hospital, place of eventual discharge, or the patients' mobility at final review. There was no difference in failure of proximal fixation: cut-out occurred in three cases with the DHS, and twice with the Gamma nail. However, in four cases fracture of the femur occurred close to the Gamma nail, requiring further major surgery. In the absence of these complications, union was seen by six months in both groups