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. Methods. A total of 18 synthetic femurs (Sawbones, Vashon Island, Washington) with comminuted pertrochanteric fractures were divided into three groups (n = 6 per group). Fracture fixation was performed using the Proximal Femoral Nail Antirotation (PFNA) implant (Synthes, Oberdorf, Switzerland; n = 6). Group 1 was subjected to unidirectional compression loading (600 N), with an elastomer (70A durometer) replacing loose fracture fragments to simulate surrounding soft-tissue tensioning. Group 2 was subjected to bidirectional loading (600 N compression loading, 120 N tensile loading), also with the elastomer replacing loose fracture fragments. Group 3 was subjected to bidirectional loading (600 N compression loading, 120 N tensile loading) without the elastomer. All constructs were tested at 2 Hz for 5000 cycles or until cut-out occurred. The medial migration distance (MMD) was recorded at the end of the testing cycles. Results. The MMDs for Groups 1, 2, and 3 were 1.02 mm, 6.27 mm, and 5.44 mm respectively, with reliable reproduction of medial migration seen in all groups. Bidirectional loading groups showed significantly higher MMDs compared with the unidirectional loading group (p < 0.01). Conclusion. Our results demonstrate significant contributions of bidirectional cyclic loading to the medial migration phenomenon in cephalomedullary nail fixation of pertrochanteric hip fractures. Cite this article: G. W. Law, Y. R. Wong, A. K-S. Yew, A. C. T. Choh, J. S. B. Koh, T. S. Howe. Medial migration in cephalomedullary nail fixation of pertrochanteric hip fractures: A biomechanical analysis using a novel bidirectional cyclic loading model. Bone Joint Res 2019;8:313–322. DOI: 10.1302/2046-3758.87.BJR-2018-0271.R1

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. Methods. Eight finite element models (FEMs), comprising four different femoral diameters, with and without blocking screws, were constructed, and unstable intertrochanteric fractures fixed with short CMNs were reproduced in all FEMs. Micromotions of distal shaft fragment related to proximal fragment, and stress concentrations at the nail construct were measured. Results. Micromotions in FEMs without a blocking screw significantly increased as nail/medullary canal mismatch increased, but were similar between FEMs with a blocking screw regardless of mismatch. Stress concentration at the nail construct was observed at the junction of the nail body and lag screw in all FEMs, and increased as nail/medullary canal mismatch increased, regardless of blocking screws. Mean stresses over regions of interest in FEMs with a blocking screw were much lower than regions of interest in those without. Mean stresses in FEMs with a blocking screw were lower than the yield strength, yet mean stresses in FEMs without blocking screws having 8 mm and 10 mm mismatch exceeded the yield strength. All mean stresses at distal locking screws were less than the yield strength. Conclusion. Using an additional anteroposterior blocking screw may be a simple and effective method to enhance fixation stability in unstable pertrochanteric fractures with a large nail/medullary canal mismatch due to osteoporosis. Cite this article: Bone Joint Res 2022;11(3):152–161

Objectives. Intramedullary fixation is considered the most stable treatment for pertrochanteric fractures of the proximal femur and cut-out is one of the most frequent mechanical complications. In order to determine the role of clinical variables and radiological parameters in predicting the risk of this complication, we analysed the data pertaining to a group of patients recruited over the course of six years. Methods. A total of 571 patients were included in this study, which analysed the incidence of cut-out in relation to several clinical variables: age; gender; the AO Foundation and Orthopaedic Trauma Association classification system (AO/OTA); type of nail; cervical-diaphyseal angle; surgical wait times; anti-osteoporotic medication; complete post-operative weight bearing; and radiological parameters (namely the lag-screw position with respect to the femoral head, the Cleveland system, the tip-apex distance (TAD), and the calcar-referenced tip-apex distance (CalTAD)). Results. The incidence of cut-out across the sample was 5.6%, with a higher incidence in female patients. A significantly higher risk of this complication was correlated with lag-screw tip positioning in the upper part of the femoral head in the anteroposterior radiological view, posterior in the latero-lateral radiological view, and in the Cleveland peripheral zones. The tip-apex distance and the calcar-referenced tip-apex distance were found to be highly significant predictors of the risk of cut-out at cut-offs of 30.7 mm and 37.3 mm, respectively, but the former appeared more reliable than the latter in predicting the occurrence of this complication. Conclusion. The tip-apex distance remains the most accurate predictor of cut-out, which is significantly greater above a cut-off of 30.7 mm. Cite this article: G. Caruso, M. Bonomo, G. Valpiani, G. Salvatori, A. Gildone, V. Lorusso, L. Massari. A six-year retrospective analysis of cut-out risk predictors in cephalomedullary nailing for pertrochanteric fractures: Can the tip-apex distance (TAD) still be considered the best parameter?. Bone Joint Res 2017;6:481–488. DOI: 10.1302/2046-3758.68.BJR-2016-0299.R1

Aim:. To audit pertrochanteric fractures treated with a cephalomedullary device in a public health institution. Method:. A retrospective 3 year analysis from January 2007 to December 2010 using theatre records and patient files. Analysis was done in terms of age, time to surgery, duration of surgery, elective or emergency, type of device used, perioperative complications and other factors. Results:. A total of 96 cases were confirmed. The average age was 67.4 years (13 to 99 years). The average time to theatre was 6.9 days. The average duration of surgery was 2 hours 59 minutes. A Trigen reconstruction nail was used in 59.4 % of the cases followed by a PFNA (26%) and others (13.6%). In 30% of cases surgery time was >3 hours and most were done electively (85.4%) during normal working hours. Revision surgery due to poor surgical technique was reported in 8 of 96 (8.3%) cases. Conclusion:. Our audit confirms that pertrochanteric fractures are common in elderly and young patients involved in high velocity trauma especially motor vehicle accidents. Pertrochanteric fractures lead to prolonged morbidity in hospital stay and theatre time. Cephalomedullary devices have reduced these complications and resulted in early rehabilitation and hospital discharge with only 8% of revisions in 3 years

Pertrochanteric fractures are, with great different from others, the most usual and important surgical fragile fractures in our society. We expose the importance of a possible prediction factor in the good outcome of a pertrochanteric fracture treated with dynamic cephalic screw. Patients and Method: We have done a retrospective study of 100 pertrochanteric fractures treated in Hospital 9 de Octubre with Gamma and Trigen Intertan locking nail. We have collected the type of fracture (depending on its stability), its epidemiology (gender, site, age, cause and concomitant illnesses), the reduction achieved, and the position of the tip of the cephalic screw (using the so called Tip-apex distance and the Cleveland squares). We have also studied possible correlations between the result and both, the reduction and position of the tip. Results: The percentage of reductions were 85% excellent, and 15% good. The average of the tip-apex distance was 15mm of average, and the most frequent position of the cephalic screw into the femoral head was inferior-center. The clinical results were excellent in 90% of patients and good in 7%, with a 3% of follow up lost because of different circumstances. Conclusion: The intraoperative assessment of the reduction achieved with the tip-apex distance, as well as the Cleveland squares, are good prediction factors to help the surgeon to anticipate the real possibilities of an excellent, good, or poor result of the fracture treatment. The clinical situation of the different patients must be taken into account in order to assess correctly the clinical result

We investigated the effect of calcitonin in the prevention of acute bone loss after a pertrochanteric fracture and its ability to reduce the incidence of further fractures in the same patient. Fifty women aged between 70 and 80 years who had a pertrochanteric fracture of the hip were randomly allocated to group A (200 IU of nasal salmon calcitonin daily for three months) or group B (placebo). Patients in group A showed a significantly higher level of total alkaline phosphatase and osteocalcin on the 15th day after injury and a significantly higher level of bone alkaline phosphatase on the 90th day after surgery. These patients also had significantly lower levels of urinary C-telopeptide (CrossLaps) on the 15th, 45th and 90th days after injury and lower levels of urinary hydroxyproline on the 15th and 45th days after injury. Patients in group A had significantly higher bone mineral density at all recorded sites except the greater trochanter at three months and one year after operation. After a four-year period of clinical observation, five patients (24%) in group B sustained a new fracture, in four of whom (20%) it was of the contralateral hip. Our findings show that calcitonin reduces acute bone loss in patients with pertrochanteric fractures and may prevent the occurrence of new fractures of the contralateral hip in the elderly

Introduction. An important factor in the internal fixation of pertrochanteric fractures is the ability to maintain postoperative reduction. Excessive postoperative sliding of the lag screw or blade may result in reduction loss. We retrospectively analyzed the relationship between postoperative reduction and sliding. Methodology. From Oct. 2009 to Sept. 2011, we treated pertrochanteric fractures using J-PFNA (Synthes) and InterTAN (Smith & Nephew) in 91 cases and 82 cases, respectively. We used postoperative radiographs to classify its reduction. Fractures were classified for its interfragmentary contact using the calcar femorale as a reference on the A-P plane while using the anterior cortex as a reference on the M-L plane. Results. PFNA cases showed greater postoperative sliding than InterTAN cases. Both demonstrated greater sliding when the proximal fragment was positioned inside the medullary canal on the M-L plane than when positioned outside or anatomically. Conclusion. Although the InterTAN can maintain greater initial stability necessary for early weight-bearing, both implants demonstrate the loss of interfragmentary contact when the proximal fragment is positioned inside the medullary canal on the M-L plane resulting in greater risk of reduction loss. In order to maintain postoperative reduction, either anatomical reduction or reducing the proximal fragment outside the medullary canal is advised; no matter what type of internal fixation implants are used

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

Controversy exists whether to treat unstable pertrochanteric hip fractures with either intramedullary or extramedullary devices. A prospective randomised control trial was performed to compare the outcome of unstable pertrochanteric hip fractures stabilised with either a sliding hip screw (SHS) or Long Gamma Nail (LGN). The hypothesis was that there is no difference in outcome between the two modes of treatment. Over a four year period, 210 patients presenting with an unstable pertrochanteric hip fracture (AO/OTA 31 A2.1/A2.2/A2.3) were recruited into the study. Eligible patients were randomised on admission to either LGN or SHS. Follow-up was arranged for three, six, and twelve months. Primary outcome measures were implant failure and implant ‘cut-out’. Secondary measures included mortality, length of hospital stay, and EuroQol outcome score. Five patients required revision surgery for implant cutout, of which three were LGNs and two were SHSs (no significant difference). There was a significant correlation between tip apex distance and the need for revision surgery. There were no incidences of implant failure or deep infection. Mortality rates between the two groups were similar when corrected for mini mental score. There was no difference between the two groups with respect to tip apex distance, hospital length of stay, blood transfusion requirement, and EuroQol outcome score. The sliding hip screw remains the gold standard in the treatment of unstable pertrochanteric fractures of the proximal femur

In a prospective, randomised study we have compared the pertrochanteric external fixator (PF) with the sliding hip screw (SHS) in 100 consecutive patients who were allocated randomly to the two methods of treatment. Details of the patients and the patterns of fracture were similar in both groups. Follow-up was for six months. Use of the PF was associated with significantly less blood loss, a shorter operating time, reduced postoperative pain, shorter hospitalisation (p < 0.001), earlier mobilisation (p < 0.001) and a reduced rate of mechanical complications (p < 0.01). Superficial infection was significantly more common with the PF (p < 0.01), but without long-term adverse consequences. There were no differences in the healing of the fracture, mortality or final functional outcome. Our results indicate that the external fixator is an effective and safe device for treating pertrochanteric fractures and should be considered as a useful alternative to conventional fixation with the sliding hip screw

The aim of the study was to compare mortalitiy and complication rate after operative treatment of pertrochanteric fractures with primary cemented arthroplasty, dynamic hip screw (DHS) or proximal femoral nail (PFN). 283 patients, which were treated betwen 1992 and 2005 for pertrochanteric femoral fractures, except pathologic fractures and a minimum age of sixty years were included. 132 of these 283 patients were treated by primary arthroplasty. Up to the end of 1999 all unstable fractures were treated by primary total hip replacement. In the year 2000 the PFN was introduced and only patients with severe osteoarthritis and osteoporosis received primary arthroplasty. I possible, more stable fractures were treated with a DHS. One year mortality was chosen as main indicator as it depends on the surgical trauma as well as the rapid return to preinjury activity and further complications. A one year period was chosen as the mortality ratio approaches that of an age matched reference population after this interval. Influencing cofactors were eliminated by stepwise logistic regression analysis. It was shown that restoration of the preoperative ambulatory level correlated with survival rate after one year. As elderly patients are often unable to cooperate with partial weight bearing, the primary stability of the device is crucial to allow early mobilisation. Mortality was significantly influenced by age, gender and comorbidities but not by fracture classification. One-year mortality was significantly higher for primary total hip replacement (34.2 %) than for internal fixation (DHS: 18.4 %; PFN 21.4 %) and hemiarthroplasty (13.3 %). Since the PFN and hemiarthroplasty were introduced the over all mortality was reduced from 29 % to 18 %. Conclusion: For stable fractures a Dynamic Hip Screw (DHS) and for unstable fractures a short proximal femoral nail (PFN) can be recommended. Primary cemented hemiarthroplasty is a viable option for treatment of intertrochanteric fractures if osteoporosis prevents from full weight bearing or if osteoarthritis makes further operations likely. Primary total hip replacement should be avoided, due to the fact that dislocation and mortality were significantly higher than in the other groups

Purpose: The purpose of this study was to analyse mechanical failures involving dismonted osteosynthesis materials implanted to fix pertrochanteric or subtrochanteric fractures with a dynamic hip screw (DHS), a Gamma nail, or a plate nail system (STACA). Material and methods: Our cohort included 16 patients among a series of 350 patients who had been treated with 240 DHS, 80 Staca nailplates, and 30 Gamma nails between 1996 and 1999. We used the Ender classification for the x-ray analysis and the Cuny criteria which describe the most common causes of dismounted material. Results: According to the defined criteria, 70/350 osteosynthesis assemblies (20%) were considered insufficient on the immediate postoperative x-rays and eventually dismounted in 16 patients. Two of these patients had major osteopaenia according to the Singh criteria and ten underwent revision because of poor clinical tolerance. These patients had six DHS (3 “swinging” cervical nails, two dismounted plates, and one screw protruding into the joint space). A protruding screw was the problem for the eight Staca nail-plates. Two Gamma nails had a “swinging” screw. These cases of dismounted material were predominantly observed in patients with Ender grade 5, 7 and 8 pertrochanteric fractures. Discussion: Our analysis of these cases revealed several important factors: 1) the quality of the fracture reduction with restitution of the medial pillar of the per-trochanteric mass; 2) central anchoring in the femoral head essential for stable fixation; 3) superior stability of the DHS in grade 1 and 6 fractures due to the greater projected surface improving hold in cancellous bone. Inversely, for subtrochanteric fractures (grade 7 and 8), centromedulary shaft anchoring with a Gamma nail reduces mechanical stress in varus and thus the risk of “swinging” screws. Finally, the monoblock construct of the Staca nail-plate, which does not have the dynamic potential of the DHS and the Gamma nail, raises a risk of protrusion, particularly in case of “internal rotation” fractures with major metaphyseal comminution (grades 4 and 5). This latter type of fixation is however very effective for simple pertrochanteric fractures with minimal comminution (grades 1 to 3). Conclusion: Material dismounting results from a series of factors related both to the material used and to the operative technique. We thus reserve the Staca nail-plate for grade 1 to 3 fractures in the Ender classification, the DHS for grades 1 to 6 and the nail-screw fixation for subtrochanteric (grade 7 and 8) fractures

Aim: To compare two implants, the Gamma Nail and the ACE Trochanteric Nail in the treatment of pertrochanteric femoral fractures. Patients and methods: Sixty patients were randomized on admission to two treatment groups. Thirty patients were treated with the Gamma nail implants , and thirty had intramedullary fixation with ACE Trochanteric NailI . The average age of these patients was 79 years. 22 patients were men and 38 women. 11 fractures were stable and 49 unstable. Patients were followed for 1 year and had a regular clinical and radiological review at 1, 3 and 6 months postoperatively. Operation time, intra-operative blood loss and blood transfusion and complications were recorded. The mobility score was used to assess the preinjury and postoperative mobility status. All the patients were operated within 24 hours after their accident and 39 of them within the first 6 hours. Results: There were no complications during the surgery. All the patients were mobilized the first 24 hours post operatively irrespectively of the fracture’s type, and weight bearing was permitted as tolerated. The mean follow up time was 8 months (range 6 to 12 months). 3 patients were lost at the follow up and 2 died. Union of the fracture was achieved in all 55 patients. There was no statistically significant difference between the two groups with regard to intraoperative blood loss and the duration of the surgery. There was no mechanical failure of the implants despite the early patients mobilization. All the patients achieved mobility status similar to the preoperative at the latest follow up. Conclusions: Based on our study, intramedullary nailing of pertrochanteric hip fractures represents a reliable method of treatment. We did not observe any differences in the two patient groups concerning the operation time, the intraoperative blood loss, the postoperative complications and the patients functional status at the latest follow up

Introduction: Screw loosening is a common complication of osteoporotic fracture fixation leading to implant loosening, fracture malunion and non-union. Because recent animal studies have shown that bisphosphonates improve implant fixation we wanted to assess whether alendronate (ALN) improves screw fixation in a clinical setting of osteoporotic fractures. Methods: Sixteen consecutive patients with AO/OTA A1 pertrochanteric fractures were selected. Inclusion criteria were: female over the age of 65, BMD T-score less than −2.5 SD. Fractures were fixed with a pertrochanteric fixator and 4 hydroxyapatite (HA)-coated screws. Two screws were implanted in the femoral head (screw positions 1 and 2) and two in the femoral diaphysis (screw positions 3 and 4). Patients were randomized to either postoperative systemic administration of ALN, 70 mg per week for 3 months (Group A) or no ALN. Fixators were removed at 3 months post-op in all patients. Results: All the fractures healed. No differences in screw insertion torque between the two groups were found. No pin loosening or infection occurred. The combined mean extraction torque of the screws implanted at positions 1 and 2 (cancellous bone) was 3181 ± 1385 N/mm in Group A and 1890 ± 813 N/mm in Group B (p < 0.001). The combined mean extraction torque of the screws implanted at positions 3 and 4 (cortical bone) was 4327 ± 1720 N/mm in Group A and 3785 ± 1181 N/mm in Group B (ns). Discussion and Conclusion: This is the first study to demonstrate in a clinical setting improved screw fixation following post-operative ALN treatment. We observed a two-fold fixation increase in the screws implanted in cancellous bone. With cortical bone, the difference in screw fixation was less marked. Besides its bone preserving ALN should be recommended as an effective solution to improve fixation in osteoporotic bone

This retrospective cohort study was conducted to investigate whether operative treatment of patients with a pertrochanteric femoral fracture outside working hours is associated with an increased risk of complications and higher mortality. During the study period 165 patients were operated on outside working hours and 123 were operated on during working hours (08.00 to 17.00). There was no difference in the rate of early complications (outside working hours 33% versus working hours 33%, p = 0.91) or total complications during follow-up (outside working hours 40% versus working hours 41%, p = 0.91). Both in-hospital mortality (outside working hours 12% versus working hours 11%, p = 0.97) and mortality after one year (outside working hours 29% versus working hours 27%, p = 0.67) were comparable. Adjustment for possible confounders by multivariate logistic regression analysis revealed no increased risk of complications when patients were operated on outside working hours. On the basis of these data, there is no medical reason to postpone operative reduction and fixation in patients with a proximal femoral fracture until working hours

Purpose: Healing may be problematic after lag screw osteosynthesis of pertrochanteric fractures in osteoporotic bone due to the greater risk of defective fixation. Acrylic cement has been proposed to reinforce the fixation of the lag screw in these patients, principally to avoid the risk of cutout, but the acrylic cement’s thermal toxicity, its poor biocompatibility, and the difficult manipulation are important drawbacks. Cortoss® is a new composite biomaterial composed of bisphenol-aglycidly (bis-GMA) which could be an attractive alternative to classical cements. Cortoss is an injectable material with mechanical properties similar to human cortical bone. The purpose of this clinical study was to describe the new method for injection the material and to assess the anchoring force and safety of Cortoss in osteoporotic patients undergoing surgical fixation of pertrochanteric fractures. Material and methods: This prospective study was approved by the local ethics committee. Twenty consecutive patients aged 70 years or more with pertro-chanteric fracture were included. The lag screw was inserted under fluoroscopic guidance, and the maximum insertion torque was measured. The screw was then unscrewed seven turns (length of the threaded head), and 2.5 cm Cortoss was injected via a polyimide catheter measuring 2.5 mm in diameter. The screw was then rescrewed in place to a troque 30% above that measured without Cortoss. Results: Eighteen women and two men, age 70 – 96 years, gave their informed consent to participate in the study. Mean maximal insertion torque without Cortoss was 1.23 Nm (min 0, max 4.8 Nm), which was increased 30% with Cortoss. Posto-operative x-rays showed that the screw head was embedded in an envelope of Cortoss and that the Cortoss had diffused into the adjacent bone. There were no adverse effects. Discussion and conclusion: Cortoss provided effective reinforcement of the fixation as demonstrated by the higher insertion torque. Cortoss can also increase the mechanical resistance of the screw-cancellous bone interface, limit fixation default, and reduce secondary displacement of the lag screw in patients with osteoporotic bone. Improved stability can also reduce immobilisation time and facilitate bone healing without increasing the risk of secondary displacement and subsequent morbidity. Due to its safety, easy use, and efficacy, Cortoss provides a better alternative than acrylic cement for reinforcement of lag screw fixation of porotic bone

Percutaneous compression plates (PCCP) used in the treatment pertrochanteric fractures are made of stainless steel, available in one size only and have two threaded oblique proximal holes for the telescopic cephalic (femoral neck) screws and three distal holes for the shaft self-tapping screws. The plate is inserted at right angles to the femoral diaphysis through a small incision and rotated so that its axis is parallel to the diaphysis. By means of small movements it is advanced along the bone, positioned between the vastus lateralis muscle and the periosteum and then fixed with the proximal and distal screws. The neck screws are telescopic and they provide a double axis fixation in the femoral neck, which increases rotational stability by allowing fracture compression and preventing collapse of the neck and subsequent cut-out. Surgery takes about 30 min and consists of two small longitudinal incisions; thus the procedure is associated with only minimal blood loss. From March 2003 to May 2004 we treated 101 patients with PCCP: 73 women and 28 men with an average age of 82 years (range 26–101 years). The average blood loss was 92.4 ml. Of the patients, 31 (29.8%) did not receive blood transfusions and of the remaining 70 patients (70.2%), 26 received one unit of blood, 35 two units and nine two units operatively and two post-operatively. When possible, weight-bearing was allowed on the third postoperative day, thus achieving a functional recovery. The healing times are similar to those of other methods. No incidence of fracture collapse or screw cut-outs was seen in this series

Purpose of the study: Osteosynthesis material adapted to a mini-invasive approach certainly reduces surgical trauma. The purpose of this work was to establish the osteosynthesis equivalence for pertrochanteric fractures using a dynamic hip screw, inserted according to the conventional technique versus a mini-invasive screw system (MISS), in terms of healing without loss of reduction. Material and methods: This was a prospective pilot study in a single centre. From May 2006 to April 2007, 78 patients (mean age 83 years, 70% women) were included (38 MISS, 40 DHS). There was one exclusion criteria: poor reduction on the orthopaedic table before incision. Radiographic and clinical follow-up for six months. The main outcome was the quality of the reduction and healing at three months. Results: Eight patients were lost to follow-up and two had died at three months. The two groups were comparable regarding mean age, ASA, fracture type, operator experience, and centring of the head screw. In the MISS group, there was a 20% reduction in blood loss, a shorter incision (9 cm) and shorter operative time (16 min). The differences were not significant. The healing rate without loss of reduction at three months was the same in both groups: 82%. There were three revisions in the MISS group: one infection and two material disassemblies. This problem disappeared with the addition of a locking screw on the nail. There were no revisions for haematoma. Discussion: There were several biases. The series was not really randomised because the type of material used depended on the availability of the instrument sets. The MISS implant evolved during the course of the study. The operators were more familiar with the DHS. Inclusion criteria were too restrictive. Multiple-injury patients with bleeding had a false impact on blood loss data. None of the differences were statistically significant. Revision for infection was not directly attributable to the material. Nail locking never failed after use of the locking screw. Conclusion: The main outcome was validated: the healing rate without reduction at three months is equivalent with the two methods (82%). A multicentric study should be conducted to confirm that the mini-incision and the MISS reduces blood loss. It could be expected that this mini-invasive approach will become the rule for osteosynthesis of these fractures with a dynamic hip screw

1. The results of treatment of 100 consecutive patients with pertrochanteric and basal fractures of the femur treated by early operative fixation with a McKee two-piece nail and plate are reviewed. 2. Technical failures are analysed and discussed. 3. The pattern of mortality is discussed and contrasted with that in a comparable series of patients treated conservatively. 4. It is concluded that early operative fixation is the method of choice in the management of these fractures, and that the McKee pin and plate is a satisfactory and reliable device for securing internal fixation