Difference in trochanteric thickness between well-aligned and malaligned polished collarless stem

BackgroundSurgical techniques and instruments are continuously evolving to improve placement of components in ideal position. We investigated if there is difference in greater trochanter thickness between the stems in satisfactory position and stems in malposition and to assess the ideal thickness of trochanter for femoral stem placement in neutral position as under reaming of trochanter can result in stem malposition.MethodsMeasurement of greater trochanteric thickness in 95 hip replacements (posterior approach) was performed by a junior doctor and two hip fellows using the trauma CAD/PACS software. The stem was considered neutral if the central axis of femur passes through the distal tip of stem in AP and in varus if the tip of stem was lateral to the femoral shaft axis.Results79 patients had stem in satisfactory position and 16 patients in varus malposition. Mean trochanteric thickness was 12.6 mm (+/−0.56 mm 95%CI, Median 12.5 mm, SD 2.5 mm) in neutral stems while mean thickness in the varus stem was 18.4 mm (+/−1.01 mm 95%CI, Median 17.8 mm, SD 2 mm). There was statistical significant difference between both groups with p< 0.0001 with intra-observer correlation at 99% between the senior personal while correlation was at 80% between the senior personnel and junior doctor. No statistically significant difference was noted in measurements between the senior personal.ConclusionsThe study confirms the significant difference in greater trochanteric thickness between the well aligned and misaligned femoral components. The study raises the possibility that trochanteric thickness can be used as an accessory surgical aid to check if sufficient broaching has been done laterally to allow the stem to be seated in neutral position with an ideal remnant thickness of 12.5 mm. A surgical instrument can be developed to measure the intraoperative thickness of the trochanter which can be a useful tool for young hip surgeons for better placement of components.     

Does a collar improve the immediate stability of uncemented femoral hip stems in total hip arthroplasty? A bilateral comparative cadaver study

The aim of this study was to compare the immediate stability of collared vs collarless uncemented femoral stems in total hip arthroplasty. A bilateral comparative study of 20 cadavers (40 hips: 20 collarless, 20 collared) was performed. Forces in the vertical and horizontal planes required to initiate subsidence of femoral stem and subsequent femoral fracture were measured. In vertical plane, subsidence began at an average force of 3129 ± 494 N for collarless stems and 6283 ± 3584 N for collared stems (P = .02). Fracture occurred at a significantly higher force for collared stems (P = <.001). In horizontal plane, subsidence began at an average force of 540 ± 170 N for collarless stems and 678 ± 206 N for collared stems (P = .01). Fracture occurred at a significantly higher force for collared stems (P = .005). Collared uncemented stems have significantly greater immediate stability than collarless. They are able to withstand greater vertical and horizontal forces before the initiation of subsidence and subsequent fracture.     

Stay Short or Go Long in Revision Total Hip Arthroplasty With Paprosky Type II Femoral Defects: A Comparative Study With the Use of an Uncemented Distal Fixating Modular Stem and a Primary Monobloc Conical Stem With 5-Year Follow-Up

BackgroundIn the revisions for Paprosky type II femoral defects, diaphyseal fixating femoral stems are commonly used. To preserve bone stock, the use of a shorter primary conical stem could be an adequate alternative. The objective of this study is to compare the results of a primary conical stem to the more commonly used diaphyseal fixating modular revision stem in revision total hip arthroplasty surgery with Paprosky type II femoral defects.MethodsA total of 59 consecutive patients with Paprosky type II femoral defects from our prospective revision registry were included. Thirty patients who received a long distal fixating modular stem (Revision Stem, Lima Corporate) and 29 patients who received a primary conical short stem (Wagner Cone, Zimmer) were prospectively followed. Minimal follow-up time was 2 years for subsidence and patient-reported outcome measures and 5 years for complications, reoperation, and revision. We compared subsidence, perioperative complications, reoperations, femoral component survival, Oxford Hip Score, EuroQol 5 Dimension, visual analog scale (VAS) for pain at rest, and VAS for pain during activity between stems.ResultsBoth groups were comparable regarding demographic, clinical, and surgery-related characteristics. We found more perioperative complications and stem revisions with the modular revision stem than with the primary conical stem. There were no statistical differences in subsidence, EuroQol 5 Dimension, Oxford Hip Score, and VAS for pain at rest or during activity between both stems.ConclusionIn revision total hip arthroplasty with Paprosky type II femoral defects, uncemented primary monobloc conical femoral stems showed the same clinical result as distal fixating modular stems with fewer complications and fewer stem revisions.     

Cement-within-cement stem exchange using the collarless polished double-taper stem

The clinical and radiographic outcomes of the cement-within-cement femoral stem exchange technique at revision hip arthroplasty were determined. Twenty-three revisions with a collarless polished double-taper stem design were prospectively monitored at up to 12 years. The most common indications for revision were recurrent dislocation and acetabular revision. Radiographic stem subsidence was measured by the Ein Bild Röentgen Analyse method. There was no stem re-revision and no radiographic loosening. Stem within cement subsidence, an intentional design feature of this stem, averaged 0.8 mm (range, 0-2 mm). The average subsidence was similar to that in primary hip arthroplasty. The excellent long-term results of cemented collarless polished taper stems for primary and revision hip arthroplasty can be extended even further by cement-within-cement exchange, which preserves the femur.     

A comparison of collared and collarless femoral components in primary cemented total hip arthroplasty: a randomized clinical trial

Between July 1986 and November 1989, 437 consecutive primary cemented total hip arthroplasties were performed using a straight-stemmed titanium alloy femoral component. Collared and collarless versions of this identical stem were randomly chosen by computer allowing a comparison between 213 collared stems (198 patients) and 224 collarless stems (209 patients). Diagnosis, sex, weight, and average age (72.8 years, collared; 72.0 years, collarless) were similar. Follow-up averaged 76 months (collared) and 72 months (collarless) with 49 patients followed for at least 10 years. Calcar-collar contact was noted in 205 hips (96%) on the initial postoperative radiograph. Early complications, including dislocations (5% each group), were similar. Late complications included 3 deep infections (2 collared, 1 collarless) and 2 postoperative femur fractures (1 each). Hip scores at the most recent follow-up averaged 91.2 and 90.1 in the collared and collarless groups. No or slight pain was noted in 93% of collared and 91.5% of collarless hips. Although no radiographic differences were noted in distal cortical hypertrophy, stem subsidence, and osteolysis, collarless hips lost significantly more medial femoral neck cortical bone (average 0.90 mm vs 0.63 mm). A higher incidence of radiolucent lines in femoral zone VI (20.7% vs 9.4%) was also noted in collarless hips.     

CT scanogram for limb length discrepancy in comminuted femoral shaft fractures following IM nailing

IntroductionLeg length discrepancy (LLD) following intramedullary nailing of femoral fractures is not uncommon. We designed a prospective study to evaluate the efficacy of routine postoperative computed tomography (CT) scanograms for evaluation of limb length discrepancy in patients with comminuted Winquist III or IV femoral shaft fractures treated with intramedullary nailing.MethodsThe study consisted of 15 patients with Winquist III and 13 with a Winquist IV femoral shaft fracture pattern with an average age of 37 years. The mechanisms of injury were motor vehicle collision (13), gunshot wound (12) and falls (three). All patients were treated with a statically locked intramedullary femoral nail (18 antegrade and 10 retrograde). A CT scanogram evaluated limb length in all patients. A discrepancy of greater than 20 mm was considered for correction during the same admission. An LLD of 15–20 mm was discussed with the patient extensively for correction.ResultsIn the 28 patients included in our study, the average limb length discrepancy was 9.1 mm with a range of ?43.5 mm short to 10.3 mm long. The LLD was less than 10 mm in 18 patients (64%), 10–15 mm in four patients (14%), 15–20 mm in three patients (11%) and more than 20 mm in three patients (11%). Measurement of discrepancy as small as 0.5 mm showed that 18 patients were fixed with shortening and in 10 patients the operated femur was longer. Tibia lengths were also evaluated separately. Though none of the tibiae had a previous fracture, only three patients (10%) had tibiae of equal length. In 13 patients, an unequal tibia partially corrected the LLD whilst in 12 it added to the discrepancy. Five patients with LLD of greater than 15 mm underwent correction.ConclusionsA postoperative scanogram in patients with comminuted femoral shaft fractures treated with intramedullary nailing is useful to evaluate LLD and allows for early intervention. The ideal length where correction is necessary remains unclear.     

Effect of dynamic hip system blade on the treatment of femoral neck fractures in elderly patients with osteoporosis

Objective：To discuss the curative effect of the dynamic hip system blade （DHS-blade） on the treatment of femoral neck fractures in elderly patients with osteoporosis.Methods：A retrospective study was conducted to analyse the clinical data of 60 elderly patients with osteoporosis who had been treated for femoral neck fractures with DHS-blade in our department between September 2012 and February 2014.There were 22 males and 38 females with a mean age of （66.8±3.2） years.According to the Singh Index Classification,all the patients＇ Singh index was below level 3.The Harris criterion and function recovery after operation were analysed.Results：All patients were followed up for 12-17 months （mean 14 months）.No femoral head necrosis,femoral neck shortening,internal fixation loosening or backing out of the nails occurred.Bone nonunion was found in one case and he had a good recovery after total hip arthroplasty.The time for fracture healing ranged from 3-6 months （average 3.5 months）.According to Harris criterion,35 cases were rated as excellent,22 good,2 fair and 1 poor.The Harris scale was significantly improved from 28.46±2.35 preoperatively to 91.98±3.26 at 6 months postoperatively （P＜0.05）.Conclusion：DHS-blade,being minimally invasive,allowing earlier postoperative exercise and avoiding the complications elicited by traditional internal fixation,is advisable for treatment of femoral neck fractured patients with osteoporosis.     

Clinical and radiological results of the collarless polished tapered stem at 15 years follow-up

We prospectively followed 191 consecutive collarless polished tapered (CPT) femoral stems, implanted in 175 patients who had a mean age at operation of 64.5 years (21 to 85). At a mean follow-up of 15.9 years (14 to 17.5), 86 patients (95 hips) were still alive. The fate of all original stems is known. The 16-year survivorship with re-operation for any reason was 80.7% (95% confidence interval 72 to 89.4). There was no loss to follow-up, with clinical data available on all 95 hips and radiological assessment performed on 90 hips (95%). At latest follow-up, the mean Harris hip score was 78 (28 to 100) and the mean Oxford hip score was 36 (15 to 48). Stems subsided within the cement mantle, with a mean subsidence of 2.1 mm (0.4 to 19.2). Among the original cohort, only one stem (0.5%) has been revised due to aseptic loosening. In total seven stems were revised for any cause, of which four revisions were required for infection following revision of the acetabular component. A total of 21?patients (11%) required some sort of revision procedure; all except three of these resulted from failure of the acetabular component. Cemented acetabular components had a significantly lower revision burden (three hips, 2.7%) than Harris Galante uncemented components (17 hips, 21.8%) (p < 0.001). The CPT stem continues to provide excellent radiological and clinical outcomes at 15?years following implantation. Its results are consistent with other polished tapered stem designs.     

Total hip arthroplasty combined with double-chevron subtrochanteric osteotomy

BackgroundSubtrochanteric femoral shortening and corrective osteotomy are regarded as an integral part of total hip arthroplasty for a completely dislocated hip or severe deformity of the proximal femur. Alternative femoral osteotomy techniques—transverse, oblique, step-cut, and V-shaped, have been described.MethodsIn this series, we performed 22 cementless total hip arthroplasties combined with double-chevron subtrochanteric osteotomies between 1997 and 2002. There were 17 females and 2 males. Their average age at the time of the operation was 59 years (range 41–74 years). Thirteen hips were completely dislocated, 8 hips needed treatment after a proximal femoral osteotomy, and there was 1 case of hip ankylosis.ResultsThe mean length of the operation was 128 min (range 80–215 min). Mean total blood loss was 1442 g (range 809–2007 g), which included both the intraoperative blood loss and postoperative blood loss. After an average of 7.6 years of follow-up, the Japanese Orthopaedic Association Hip Score improved from 48 to 79. Three types of complication were observed. There were 4 early dislocations, 3 proximal splits, and 1 nonunion at the osteotomy site.ConclusionsOur study shows that acceptable results are obtained from double-chevron subtrochanteric osteotomy for subtrochanteric femoral shortening and corrective osteotomy. However, total hip arthroplasty combined with subtrochanteric osteotomy is a technically demanding treatment option.     

Pre-operative digital templating in cemented hip hemiarthroplasty for neck of femur fractures

Pre-operative digital templating allows the surgeon to foresee any anatomical anomalies which may lead to intra-operative problems, and anticipate appropriate instruments and implants required during surgery. Although its role is well-established in successful elective total hip arthroplasty, little work has been done on its use in hip hemiarthroplasty in neck of femur fractures. We describe our initial experience of digital templating in 40 consecutive patients who have undergone cemented hip hemiarthroplasty, assessing templating accuracy between templated implant sizes to actual implant sizes. 81% of implanted heads were templated to within two head sizes, and 89% of implanted stems were templated to within two sizes. Although there was a moderately strong correlation of 0.52 between templated and actual head sizes, this correlation was not demonstrated in femoral stem sizes. Mean leg length discrepancy was −2.5 mm (S.D. 8.5), and the mean difference in femoral offset between the operated and non-operated hip was −1 mm (S.D. 4.4). Digital templating is a useful adjunct to the surgeon in pre-operative planning of hip hemiarthroplasty in the restoration of leg length and femoral offset. However, its accuracy is inferior to that of elective total hip arthroplasty.     

Closed reduction and internal fixation versus total hip arthroplasty for displaced femoral neck fracture

Objective： To compare the clinical effects between closed reduction and internal fixation （CRIF） and total hip arthroplasty （THA） for displaced femoral neck fracture. Methods： In this prospective randomized study, 285 patients aged above 65 years with hip fractures （Garden III or IV） were included from January 2001 to December 2005. The cases were randomly allocated to either the CRIF group or THA group. Patients with pathological fractures （bone tumors or metabolic bone disease）, preoperative avascular necrosis of the femoral head, osteoarthritis, rheumatoid arthritis, hemiplegia, long-term bed rest and complications affecting hip functions were excluded. Results： During the had significantly higher 5-year follow-up, CRIF group rates of complication in hipjoint, general complication and reoperation than THA group （38.3% vs. 12.7%, P〈0.01; 45.3% vs. 21.7%, P〈0.01; 33.6% vs. 10.2%, P〈0.05 respectively）. There was no difference in mortality between the two groups. Postoperative function of the hip joint in THA group recovered favorably with higher Harris scores. Conclusion： For displaced fractures of the femoral neck in elderly patients, THA can achieve a lower rate of complication and reoperation, as well as better postoperative recovery of hip joint function compared with CRIF.     

No increased stem subsidence after arthroplasty in young patients with femoral head osteonecrosis:41 patients followed for 1–9 years

Background?Poor bone stock in patients with osteonecrosis of the femoral head may be a reason for poor outcome after hip replacement. One way of studying bone quality is to measure implant migration. We thus investigated the clinical and radiographic results of cementless THR in younger patients with femoral head osteonecrosis.

Patients and methods?We studied hips in 41 patients (mean age 48 (25–63) years) with a cementless hip arthroplasty after late stage osteonecrosis. Clinical evaluation was by the Harris hip score, the WOMAC score and the SF-36 score. Stem subsidence was measured with the Ein Bild Roentgen Analyse femoral component analysis (EBRA-FCA) at 3, 12, 24, 60, and 72 months after operation. The average duration of follow-up was 7(1–9) years, with less than 2 years for 2 patients.

Results?There was no revision of any hip. No radiographic or clinical stem loosening was seen. After 60 months, the cementless stems showed a median subsidence of –0.7?mm (95% CI: –0.9 to –0.2). No femoral osteolysis occurred. Femoral radiolucent lines, all < 1?mm, were seen in 10 hips. At the latest follow-up the Harris hip score was 83 (23–100) points.

Interpretation?Our findings for porous-coated stems in patients with femoral osteonecrosis indicate no greater risk of stem subsidence and rate of osteolysis after an average of 7 years follow-up. Thus, we continue to use uncemented stems in younger patients with femoral osteonecrosis. However, continued follow-up will be necessary to evaluate the long-term outcome.     

Total hip replacement for neck of femur fracture: Comparing outcomes with matched elective cohort

IntroductionCurrent literature suggests that total hip replacement (THR) is superior to hemiarthroplasty (HA) for neck of femur fracture in selected group of patients. The outcomes of THR undertaken for trauma setting remain unclear when comparing with elective THR. We compared the outcomes of THR trauma cohort with best-matched elective cohort.MethodsWe retrospectively reviewed 102 patients that underwent THR due to trauma from 2011 to 2013. We had access to 90 cases with complete records. Another 90 matched elective cases were obtained from local arthroplasty database. The elective cases were matched for gender, surgical approaches, surgeon’s grade, types of implant, patient’s age at operation date of ±5 years and operation date of ±60 days. Subsequently, the selection criteria were relaxed to patient’s age at operation date of ±10 years and operation date of ±60 days. Unmatched cases were excluded. Complications and death rate were compared.ResultsThe average age for both cohorts was 70 years. The trauma cohort had statistically significant lower BMI and longer hospital stay (p = 0.001). The Functional Comorbidity Index (FCI) and Charlson Age Comorbidity Index (CACI) were the same for both cohorts, reflecting an active patient selection for THR in our centre. The trauma cohort had higher surgical complication rate (9% vs 4%), particularly higher dislocation rate (7% vs 1%); and higher medical complication rate (32% vs 6%). These were consistent with the literature. Contrary to literature, the trauma cohort had six dislocations that five of them were done via anterolateral approach. Among the eight trauma cases with surgical complications, six cases were performed by trainees. The cause of surgical complications remains unclear due to the nature of retrospective study. The trauma cohort had higher death rate than the elective cohort (14% vs 4%), with one post-operative cardiac arrest in the trauma cohort. The rest were non-orthopaedic related deaths, ranging between four months to four years.ConclusionA more robust way of selecting trauma patients for THR is warranted to reduce morbidity and mortality. Follow-up for the trauma cohort is warranted, as the patients are likely to outlive the implants.     

Bicortical Contact Predicts Subsidence of Modular Tapered Stems in Revision Total Hip Arthroplasty

BackgroundWe describe the intraoperative parameters that affect stem subsidence rates in tapered modular femoral stems for revision total hip arthroplasty (THA). We also determine the effect of the stem bicortical contact on subsidence rates and whether there is a minimum threshold bicortical contact that must be achieved to avoid the complication of subsidence.MethodsThis is a retrospective cohort study consisting of 109 hips in 105 patients (53 males and 52 females) at a minimum of 2 years of follow-up. All revisions were carried out for Paprosky type 3A and 3B femoral deficits. Clinical outcomes included the indication for revision, aseptic re-revision surgery, specifications of the stem inserted, and specifications of the femoral head and acetabular components implanted. Radiographic outcome measures included subsidence (mm) and bicortical contact (mm).ResultsUsing multivariate regression analysis, 3 parameters were associated with an increased rate of stem subsidence. A reduced bicortical contact distance (P < .001) and a stem length of ≤155 mm (P < .001) were both associated with higher subsidence rates. We also demonstrated a novel threshold of 20-mm bicortical contact which must be achieved to significantly reduce subsidence rates in these modular femoral stems for revision THA.ConclusionSubsidence rates of modular tapered femoral stems for revision THA can be significantly reduced by increasing the initial bicortical contact of the stem within the diaphysis and the overall length of the femoral stem >155 mm. We describe a minimum threshold bicortical contact distance of 20 mm that should ideally be exceeded to significantly reduce the risk of stem subsidence within the femoral canal.     

Metal-on-metal hip replacement using Metasul cups cemented into Muller reinforcement rings after a mean 5-year (3-8) follow-up: improvement of acetabular fixation by comparing with direct cementation to bone

Purpose of the studyEarly loosening, before a three-year follow-up, has been observed with cemented cups having a metal-on-metal insert in a polyethylene cup. The metal-on-metal bearing has been incriminated as the source of the problem because of its rigidity (particularly for small cups measuring less than 50 mm) and the creation of stress conditions unfavorable for a cemented fixation. The purpose of this retrospective study was to determine whether this phenomenon is observed when the cement is fixed not directly into the bone, but via a Muller reinforcement ring.Material and methodsFrom 1998 to 2004, 23 arthroplasties using a cemented Metasul^® cup in a reinforcement ring were implanted in 22 patients (16 women and six men) aged on average 44 years (range 24–56 years). The series included six primary total hip arthroplasties (three for dysplasia, two for protrusions, one for rheumatoid arthritis and one for arthritic degradation) and seventeen revisions (two septic). The Metasul? cup (Zimmer-Centerpulse) combined a 28 mm modular head anchored in a femoral implant (two cemented, 21 pressfit) and a polyethylene cup with a Metasul^®? insert (13 of 23 measuring < 50 mm). In all cases, the cup was fixed with low-viscosity cement in a Myller metal reinforcement ring fixed with screws (Zimmer-Centerpulse). All patients were reviewed clinically and radiographically at a mean 5-year follow-up (range 3–8 years). Acetabular and femoral fixation were analysed (search for lucency and implant migration).ResultsRevision was not necessary in any patient for failure of the acetabular fixation. The mean Postel-Merle-d’Aubigné score improved from 12.9 points (range 7–17) to 17.5 points (range 16–18). The radiographic analysis did not reveal any sign of lucency between the cup and ring, nor any migration of the ring. There was no evidence of femoral osteolysis but one femoral revision was needed due to fracture of the lateral cortical identified six weeks after implantation.Discussion and conclusionCementing the metal-on-metal cup into a reinforcement ring can avoid the risk of loosening observed after direct cementing into bone. In our study, the large number of small cups (13/23) would have been expected to produce a high rate of acetabular lucent lines and/or a high rate of early revision, as reported by others, as early as 24 months. Our series was also different from others by the use of pressfit femoral implants in most patients, which should reduce the risk of cement debris in the bearing. Longer follow-up will be necessary to confirm the good results observed to date which suggest that direct cementing of the cup into the bone should be incriminated rather than the metal-on-metal bearing to explain the reported failure of cemented Metasul? cups.     

Ten-year survival of the MS-30 matt-surfaced cemented stem

The Morscher-Spotorno (MS-30) femoral stem is a stainless-steel, straight, three-dimensionally tapered, collarless implant for cemented fixation in total hip replacement.We report the results at ten years of a consecutive series of 124 total hip replacements in 121 patients with the matt-surfaced MS-30 stem and an alumina ceramic head of 28-mm diameter. All the stems were fixed with Palacos bone cement with gentamicin using a modern cementing technique. They were combined with an uncemented, press-fit cup. The mean period of observation was 10.2 years (8.3 to 12.1) and no patient was lost to follow-up. Twenty-seven patients (22%) died with the implant in situ. Nine could only be interviewed by telephone. We included 85 patients with 88 hips in the clinical and radiological follow-up examinations.None of the stems or cups had been revised. The Harris hip score was excellent or good in 97% (85 hips) and moderate in 3% (three hips). Radiologically, six hips (6.8%) had osteolysis adjacent to the stem, mostly in Gruen zone 7. Twenty (22.7%) showed one or more radiolucent lines. Twenty-two stems (25%) had subsided by 2 mm to 5 mm. In these cases two showed osteolysis (9.1%) with subsidence and four without (6.1%). Radiolucent lines were seen in seven with migration (31.8%) and in 13 without (19.7%). No infections and no acetabular osteolysis were observed.The clinical results were excellent with survivorship after ten years of 100% and only a slightly statistically non-significant higher rate of osteolysis and radiolucency in cases of subsidence.     

Multi-center study of use of the Exeter stem in Japan: evaluation of 1000 primary THA

BackgroundThe Exeter stem was introduced to the Japanese market in 1996. Since then, owing to excellent clinical results, the number of stems used has increased year by year and more than 2000 stems were implanted in 2009. The objective of this study was to prove the efficacy of the Exeter stem for Japanese patients by evaluating the short-term results of four major dedicated hip centers.MethodsWe performed a retrospective study of clinical and radiographic results of 1000 primary total hip arthroplasties (THA) performed using the Exeter stem on 881 patients who were followed-up for at least 2 years after surgery. The average age of the patients at operation was 62.3 years (range 23–89 years). Mean postoperative follow-up period was 4.0 (range 2–9) years.ResultsThirty postoperative complications were observed, including 9 infections, 14 dislocations, 5 cases of deep vein thrombosis, and 2 cases of sciatic nerve palsy. No symptomatic pulmonary embolization or femoral fractures were observed. Re-operations for infection and dislocation were performed in 8 and 6 hips, respectively. According to Barrack's classification, the postoperative cementing grade was judged as A for 735 hips, B for 246 hips, and C for 4 hips. At final follow-up, no radiolucent line was observed at the bone–cement interface. Cortical hypertrophy was observed in 9.5 % of cases in Gruen zones 2–6. Kaplan–Meier survival analysis predicted 100 % survival at 5 years when a radiolucent line at the bone–cement interface of the femur was used as the endpoint, 98.8 % when re-operation was required for any reason.ConclusionsThis study revealed that excellent short-term results were achieved by fixing the Exeter stem with modern cementing techniques for primary THA in Japanese patients.     

Recalled pain scores are not reliable after acute trauma

IntroductionPain research in emergency settings can be problematic, as data collection is logistically difficult and pain levels are often poorly documented. Short-term recall of acute pain has been evaluated in postoperative, labour and procedural pain, with variable reported accuracy. The reliability of pain recall in trauma resuscitation patients is unknown. This study aims to determine the accuracy of short-term pain recall 1–2 days after trauma.MethodsProspective, cohort study of trauma resuscitation patients transported by ambulance to a major trauma centre. Patients with haemodynamic instability (SBP < 90, HR > 120) or GCS < 14 on arrival were excluded. Momentary pain scores were measured on an 11-point verbal numerical rating scale by paramedics during prehospital management. Patients were evaluated within 48 h of injury on the recall of their initial pain, pain during transport, and lowest pain score achieved by prehospital analgesia. Spearman's rank correlation and Bland–Altman tests were used to compare ambulance and hospital data.Results88 trauma resuscitation patients (mean age 44 years ± 18 SD, male 74%, mean ISS: 7 ± 5 SD) were enrolled over a 5 month study period. Comparison of immediate and recalled pain scores produced Spearman's correlation coefficients of 0.71 for initial pain, 0.56 for pain during transport, and 0.45 for minimum pain scores.DiscussionIn our study patients did not accurately recall their pain levels 1–2 days after acute trauma. The results suggest that retrospective pain ratings are not reliable in trauma patients.     

Effect of beta-blockers on bone mass and biomechanical parameters of the femoral neck in males with acute myocardial infarction

ObjectivesEvaluate the effect of cardioselective β-blockers on bone mass and biomechanical properties of the femoral neck in males with acute myocardial infarction.MethodsForty males with acute myocardial infarction were studied during one year. Seventy-five percent of the patients (30 patients) were treated with cardioselective β-blockers and 10 were not similarly treated. A hip densitometry was performed upon release and one year later. The BMD was measured in the femoral neck and in biomechanical elements obtained by DXA.ResultsBoth groups had similar clinical conditions at the beginning of the study and after a one-year follow-up. No differences in the BMD (0.934 ± 0.12 vs. 0.921 ± 0.14) were observed in the group without β-blockers or in the group with β-blockers (0.980 ± 0.12 vs. 0.977 ± 0.12). No differences were observed in the measured structural parameters.ConclusionThe cardioselective β-blockers do not modify bone mass or the structural bone parameters in males with acute myocardial infarction.     

Computer navigation in the reduction and fixation of femoral shaft fractures: a randomized control study

ObjectivesWe investigated the accuracy of reduction of intramedullary nailed femoral shaft fractures in human cadavers, comparing conventional and computer navigation techniques.MethodsTwenty femoral shaft fractures were created in human cadavers, with segmental defects ranging from 9 to 53 mm in length (Winquist 3–4, AO 32C2). All fractures were fixed with antegrade 9 mm diameter femoral nails on a radiolucent operating table. Five fractures (“Fluoro” group) were fixed with conventional techniques and fifteen fractures (“Nav 1” and “Nav 2” groups) with computer navigation, using fluoroscopic images of the normal femur to correct for length and rotation. Postoperative CT scans compared femoral length and rotation with the normal leg.ResultsMean leg length discrepancy in the computer navigation groups was smaller, namely, 3.6 mm for Nav 1 (95% CI: 1.072 to 6.128) and 4.2 mm for Nav 2 (95% CI: 0.63 to 7.75) vs. 9.8 mm for Fluoro (95% CI: 6.225 to 13.37) (p < 0.023). Mean rotational discrepancies were 8.7° for Nav 1 (95% CI: 4.282 to 13.12) and 5.6° for Nav 2 (95% CI: ?0.65 to 11.85) vs. 9.0° for Fluoro (95% CI: 2.752 to 15.25) (p = 0.650).ConclusionsComputer navigation significantly improves the accuracy of femoral shaft fracture fixation with regard to leg length, but not rotational deformity.