Dual-mobility tripod cup for revision hip arthroplasty: long-term (five to fourteen years) evaluation of a new generation cementless implant

PURPOSE

The aims of this study were to evaluate the survivorships of a new generation cementless DMC with tripod additional fixation in revision total hip arthroplasty and complications at a minimum five year follow-up.

METHODS

One hundred and fifteen revisions (THA) treated with tripod DMC performed between 2009 and 2015 were included in this retrospective study. Acetabular defects were classified as Paprosky 1 (n = 38, 33%), 2 (n = 75, 65%) or 3 (n = 2, 2%). Unipolar or bipolar revision was performed for the following indications: aseptic acetabular loosening (63%), infection (14%), aseptic bipolar loosening (11%), instability (4%), aseptic femoral loosening (3%), ALVAL (3%) and iliopsoas impingement (2%). Mean follow-up was 9.4 years ± two (range, 5 to 14).

RESULTS

At the final follow-up, a single episode of dislocation occurred within three months after the procedure (0.8%) with no revision. Three cases of aseptic loosening were diagnosed (2.6%). Four infections (3.5%) required reoperation: three required a two stage bipolar revision; one was treated by DAIR procedure. At the latest follow-up, the survivorship of the acetabular cup for aseptic loosening was 98% [95% CI (91.2-99.4)] and for any reasons was 94.4% [95% CI (90.1%-98.9%)]; the mean HHS improved from 60 points (range, 18-94 points) to 83 points (range, 37-100 points) (p < .001).

CONCLUSION

This study reports a low complication rate in favour of the use of a tripod DMC in revision THA with a satisfactory survivorship at a ten year follow-up.

Revision of total hip arthroplasty by long locking stem with fully hydroxyapatite-coated modular metaphysis (Reef™): A continuous series of 78 cases at a minimum 2-year follow-up

INTRODUCTION

Since the Wagner and Vives stems were introduced in the 1980s, the range of uncemented implants for femoral revision has grown with increasing demand. Cementless modular implants with a wide range of lengths and diameters improved adaptation to the bone and secondary metaphyseal integration. Data are sparse for the Reef™ locking stem (Depuy-Synthes, Saint-Priest, France) and we therefore conducted a retrospective study at more than 2 years' follow-up, in a continuous series of total hip arthroplasty (THR) revision procedures using this long fully-hydroxyapatite-coated modular locking stem, assessing (1) implant survival, (2) clinical and functional results, and (3) radiographic results.

HYPOTHESIS

The study hypothesis was that all-cause≥2-year survival is>90%.

PATIENTS AND METHODS

Between 2007 and 2018, 413 femoral stem exchanges were performed in our center, a Reef™ model being needed in 93 cases. Etiologies comprised: Vancouver B2 or B3 periprosthetic fracture (57%, n=53), aseptic loosening (33%, n=30), septic loosening (10%, n=9) and 1 case of aseptic non-union under the stem (1%, n=1). Clinical and functional assessment used Harris Hip Score (HHS), Postel Merle d'Aubigné score (PMA) and Oxford-12 Hip Score (OHS). Radiographic assessment used immediate postoperative views and last follow-up radiographs, assessing osseointegration, filling index and stress shielding. Implant survival was estimated following Kaplan-Meier with 95% confidence intervals.

RESULTS

Mean follow-up was 6±3 years (range, 2-12). Last follow-up included 78 cases for analysis (12 deaths [13%] and 3 patients lost to follow-up before 2 years [3%]). Ten-year Reef™ implant survival was 98.7% (95% CI: 96.3-100) free of aseptic loosening (n=1) and 94% (95% CI: 87-100) for all causes (n=3). The failures related to aseptic loosening involved femoral stem fracture away from the modular part; the 2 cases of septic loosening did not undergo reimplantation for medical reasons. Preoperatively (scheduled surgeries, excluding periprosthetic fractures: n=40), mean HHS was 43±12 and 77±12 at last follow-up (81±13 in scheduled surgery [n=40] and 73±11 in emergency surgery for periprosthetic fracture [n=53]), mean PMA score was 13±2 and mean OHS was 26±9. The infection rate was 11% (n=9) including 7.6% new infection (n=6). The dislocation rate was 6% (n=5). The radiographic stress shielding rate was 11% (n=9) and significantly associated with low metaphyseal filling index (76±7% vs. 83±8% [p=0.009]).

DISCUSSION

Like other recent data, the present good survival results support the trend for uncemented stems in femoral revision, as encouraged by the 1999 symposium of the French Society of Orthopedic Surgery and Traumatology (SoFCOT). Primary diaphyseal fixation enables secondary metaphyseal integration on an implant with modularity ensuring good bone adaptation. Close contact between the bone and hydroxyapatite surfaces is a key-point in the surgical strategy.

LEVEL OF EVIDENCE

IV, retrospective study.

Extended Trochanteric Osteotomy in Revision Total Hip Arthroplasty

Background

Removal of well-fixed femoral components during revision total hip arthroplasty (THA) can be difficult and time-consuming1, leading to numerous complications, such as femoral perforation, bone loss, and fracture. Extended trochanteric osteotomies (ETOs), which provide wide exposure and direct access to the femoral canal under controlled conditions, have become a popular method to circumvent these challenges. ETOs were popularized by Wagner (i.e., the anterior-based osteotomy), and later modified by Paprosky (i.e., the lateral-based osteotomy)2.

Description

The decision to utilize the laterally based Paprosky ETO versus the anteriorly based Wagner ETO is primarily based on surgeon preference, the location and type of in situ implants, and the osseous anatomy. Typically, a laterally based ETO is most facile in conjunction with a posterior approach and an anteriorly based ETO is most commonly paired with a lateral or anterolateral approach. Attention must be paid to maintaining vascularity to the osteotomy fragment, including minimizing stripping of the vastus lateralis from the osteotomy fragment and maintaining abductor attachments to the osteotomy fragment. When utilizing a laterally based ETO, the posterior border of the vastus lateralis must be carefully elevated to provide exposure for performance of the osteotomy. When an anteriorly based osteotomy is performed, the surgeon may instead extend the abductor tenotomy proximally with use of a longitudinal split of the vastus lateralis distally, which helps to keep the anterior and posterior sleeves of soft tissue in continuity. In either approach, dissection of the vastus lateralis involves managing several large vascular perforators. We prefer performing careful blunt dissection to identify the perforators and prophylactically controlling them, with ligation of large vessels and electrocautery of smaller vessels. Vascular clips are also available in case difficult-to-control bleeding is encountered. In general, an oscillating saw (with preference for a thin blade) is utilized to complete the posterior longitudinal limb of the ETO, extending approximately 12 to 16 cm distally from the tip of the greater trochanter. Although a 12 to 16-cm zone is required to maintain maximum vascularity to the osteotomized fragment, the osteotomy length must ultimately be determined by (1) the length of the femoral component to be removed; (2) the presence of distal bone ingrowth, ongrowth, or cement; and (3) the presence of distal hardware or stemmed knee components. A smaller oscillating saw is then utilized to complete the transverse limb at the previously identified distal extent. A high-speed pencil-tip burr is utilized to complete the corners of the osteotomy in a rounded configuration, and a combination of saws and pencil-tip burrs is utilized to create partial proximal and distal anterior longitudinal limbs of the osteotomy to the extent allowed by the soft-tissue attachments. The anterior longitudinal limb may be further weakened in a controlled fashion with use of serial drill holes. The anterior longitudinal limb then undergoes controlled fracture by placement of 2 to 4 broad straight osteotomes in the posterior longitudinal limb. These osteotomes are carefully levered anteriorly in unison with a gentle, steady force. After the ETO is completed, intramedullary prostheses, hardware, and cement are removed; the acetabulum is addressed as needed; and a final femoral stem is implanted, if appropriate. After completion of the osteotomy, the osteotomized fragment must be retracted gently, with care taken to avoid a fracture and maintain vascularity. To this end, debridement of the endosteum of the osteotomized fragment, including any cement removal, should be avoided until the end of the procedure, when the osteotomy is ready to be closed. Our preferred method for closure is to place 1 prophylactic cable 1 cm distal to the osteotomy, 1 to 2 cables along the diaphyseal segment of the osteotomy, and 1 Luque wire above the less trochanter. A Luque wire is our specific choice for the location above the lesser trochanter because it sits in the effective joint space; however, the use of Luque wires distal to the lesser trochanter is also acceptable. A strut allograft or locking plate can be utilized to reinforce the osteotomy in rare cases or to bridge interprosthetic stress risers. Trochanteric implants are typically avoided because of the low rate of clinically relevant trochanteric migration with this closure technique and because of the high rate of symptomatic implants with trochanteric claws or plates.

Alternatives

An alternative osteotomy of similar exposure is the transfemoral osteotomy. Additionally, a variety of non-extended trochanteric osteotomies, such as trochanteric slide osteotomies, offer more limited exposure.

Rationale

Femoral surgical exposure for revision THA can be aided by performing transfemoral osteotomies, but these provide less precise control of the separate proximal femoral osteotomized segment(s), and healing and fixation can be less reliable. Less invasive osteotomies such as non-extended trochanteric osteotomies typically do not provide adequate exposure in challenging cases for which ETO is being considered.

Expected Outcomes

ETOs have high union rates, and notable trochanteric migration is infrequent. The most common complications are fracture of the osteotomy fragment intraoperatively or postoperatively. Radiographic and clinical union is achieved in 98% of patients. The mean proximal trochanteric osteotomy fragment migration prior to union is 3 mm. ETO fragment migration of >1 cm occurs in just 7% of hips. Postoperative greater trochanter fractures occur in 9% of hips. The 10-year survivorship free of revision for aseptic femoral loosening, free of femoral or acetabular component removal or revision for any reason, and free of reoperation for any reason is 97%, 91%, and 82%, respectively3.

Important Tips

Attention should be paid to patient anatomy, deformity, surgical approach, and implant type when choosing to perform a laterally based Paprosky or anteriorly based Wagner ETO.Appropriate length of the posterior longitudinal limb of the ETO is approximately 12 to 16 cm distally from the tip of the greater trochanter.Attention must be paid to maintaining vascularity to the osteotomy fragment, including minimizing stripping of the vastus lateralis from the osteotomy fragment and maintaining abductor attachments to the osteotomy fragment.A high-speed pencil-tip burr should be utilized to complete the corners of the osteotomy in a rounded configuration in order to avoid stress risers.The anterior longitudinal limb is completed by controlled fracture of the remaining intervening segment in order to maintain vastus lateralis attachments and vascular supply to the osteotomy fragment.The ETO is closed with use of cerclage cables and/or double-stranded Luque wires, typically utilizing a total of 3 to 4 in order to obtain secure fixation without compromising local biology.

Acronyms and Abbreviations

MFT = modular fluted tapered.

Analysis of an explanted dual mobility cup after 21 years, parabolic wear pattern: A case report

CASE

A dual mobility cup was implanted in 1983 in a 43-year woman. After 31 years of normal function, we analysed the explanted materials with modern techniques.

CONCLUSION

Volumetric wears of the small and large articulations of the dual-mobility construct were similar. For the first time, we demonstrated that the dual-mobility liner underwent parabolic (not linear) wear during the period of implantation.

Tarsal Tunnel Syndrome: Outcome According to Etiology

Surgical results in tarsal tunnel syndrome are variable, and etiology seems to be a factor. Three possible etiologies can be distinguished. The aim of the present study was to compare surgical results according to etiology. Three continuous retrospective series (45 patients overall) of tarsal tunnel syndrome were compared. Group 1 presented a permanent intra- or extra-tunnel space-occupying compressive structure. Group 2 presented intermittent intra-tunnel venous dilatations. Group 3 comprised idiopathic tarsal tunnel syndrome. The mean follow-up was 3.6 +/- 1.8 years. The main endpoint was subjective postoperative improvement on Likert scale. Group 1 reported greater improvement than groups 2 and 3. Preoperative neuropathy on ultrasound was associated with poorer improvement, which was not the case for neuropathy on electromyography. Surgical treatment of tarsal tunnel syndrome provides better results in etiologies involving structural compression.

Cementless hydroxyapatite-coated stem with dual mobility and posterior approach in over-80 year-old patients with osteoarthritis: Rates of dislocation and periprosthetic fracture at a mean 8 years' follow-up

BACKGROUND

Straight cementless stems are common in primary total hip arthroplasty (THA) in the elderly, but controversial due to higher risk of loosening and periprosthetic fracture (PPF). Apart from registries, results for the Corail implant and dual mobility (DM) in over-80 years-old are not known, notably in case of systematic association to a DM cup. We therefore performed a retrospective analysis of Corail implants in patients aged≥80years at implantation for osteoarthritis of the hip, assessing 1) PPF rate and survival for cementless straight stems associated to DM cups, 2) complications, and dislocation in particular, and 3) clinical scores.

HYPOTHESIS

PPF and dislocation rates are low in THA with cementless straight stem associated to DM cup in patients aged≥80years.

PATIENTS METHODS

A retrospective study was conducted in our department for the period July 2007 to December 2012. Inclusion criteria were age≥80years, with primary THA for osteoarthritis. Exclusion criteria were revision procedure and femoral neck fracture. One hundred and twenty-eight consecutive THAs were included, in 120 patients, with a minimum 5years' follow-up. Clinical results were assessed on Harris Hip Score (HHS) and Oxford Hip Score (OHS). Data were collected for PPF or dislocation and other complications.

RESULTS

At a mean 8±1 years' follow-up (range, 5-10 years), 66 patients (55%, for 68 hips) were alive, 48 (40%, for 54 hips) had died, and 6 (5%, for 6 hips) were lost to follow-up. Median age at surgery was 83years (range, 80-93years). Mean OHS at last follow-up was 41±6 (range, 21-48) and HHS 83±14 (range, 23-100) with mean gain of 32 points (95% CI, [28-36]; p<0.001)). There were 2 cases (1.6%) of PPF, at 2 and 65months, and no dislocations or cases of aseptic loosening. There were 2 cases (1.6%) of intraoperative calcar fracture, treated by wire cerclage with immediate complete weight-bearing, without further complications. With death as a competing risk, cumulative 10-year incidence of femoral stem revision was 1.6% [95% CI: 0.4-6.5], and cumulative incidence of all-cause revision was 4.1% [95% CI: 1.7-9.7].

DISCUSSION

In an over-80 year-old population, primary THA with straight cementless stem and 2nd generation dual mobility cup was an effective option with low risk of PPF or dislocation after a minimum 5-year of follow-up.

LEVEL OF EVIDENCE

IV; retrospective study.

Incidence and risk factors for bilateral proximal femoral fractures

BACKGROUND

Proximal femoral fractures (PFFs) are a public health issue due to their high frequency. The frequency of a second PFF on the other side is estimated at 10%. This estimation is controversial, however, and the risk factors have not been evaluated in a large population of French patients. The objective of this retrospective case-control study was to determine: (1) the incidence of second PFFs and (2) their risk factors.

HYPOTHESIS

The incidence of second PFFs is >2% after 1 year and >5% after 3 years.

MATERIAL AND METHODS

We conducted a case-control study in a population of consecutive patients managed surgically for PPF at the Lyon Sud Hospital between 2013 and 2014. We analysed the following clinical factors: age, sex, body mass index (BMI), institutionalisation, the Parker score, the American Society of Anesthesiologists score (ASA), comorbidities, and the use of psychoactive drugs.

RESULTS

We included 474 PFFs (trochanter, n=240 and neck, n=234) of which 36 were bilateral. The contralateral fracture occurred within 1 year of the first fracture in 6/474 (1.3%) cases and within 3 years in all 36 cases (7.6%). The case-control study comprised 49 cases with bilateral PFF and 161 controls with no second hip fracture within 3 years. Risk factors for a second hip fracture were age older than 90 years (odds ratio [OR]=5.44; 95% confidence interval [95%CI], 112-2642 (p=0.002)) and a history of heart disease (OR, 2.18; 95%CI, 1.06-4.47 [p=0.03]). A Parker score≥6 was protective (OR, 0.84; 95%CI, 0.71-0.99 [p=0.03]). Mortality after 3 years was 42% (201/474), and 13% (63/474) of patients were lost to follow-up.

DISCUSSION

Age older than 90 years, a Parker score below 6, and a history of heart disease are risk factors for a second PFF within 3 years after the first PFF.

LEVEL OF EVIDENCE

III; case-control study.

Coxiella burnetti prosthetic joint infection in an immunocompromised woman: iterative surgeries, prolonged ofloxacin-rifampin treatment and complex reconstruction were needed for the cure

Background

Q fever is a zoonotic disease caused by the bacterium Coxiella burnetii, a strictly intracellular pathogen that can cause acute and chronic infection. Chronic Q fever can occur in immunocompetent as well as in immuno-compromised hosts, as a persistent localized infection. The main localizations are endocardial, vascular and, less frequently, osteoarticular. The most frequent osteoarticular form is spondyliscitis. Recommended treatment is combined doxycycline and hydroxychloroquine for 18 months, with cotrimoxazole as another option. Coxiella burnetti infection has been implicated in rare cases of prosthetic joint infection (PJI), and the medical and surgical management and outcome in such cases have been little reported.

Case presentation

We report an unusual case of chronic Q fever involving a hip arthroplasty in an immunocompromised woman treated with tumor necrosis factor (TNF)-α blockers for rheumatoid arthritis. Numerous surgical procedures (explantation, “second look”, femoral resection and revision by megaprosthesis), modification of the immunosuppressant therapy and switch from doxycycline-hydroxychloroquine to prolonged ofloxacin-rifampin combination therapy were needed to achieve reconstruction and treat the PJI, with a follow-up of 7 years.

Conclusions

Coxiella burnetti PJI is a complex infection that requires dedicated management in an experienced reference center. Combined use of ofloxacin-rifampin can be effective.

Safety and efficacy of a strategy of vitamin K antagonist reversal with prothrombin complex concentrates compared to vitamin K in patients with hip fracture

Background:

Increased preoperative delay in patients with hip fractures may be responsible for increased morbidity and mortality. We hypothesized that a strategy of reversal of vitamin K antagonist (VKA) by prothrombin complexes concentrates (PCCs), as compared to vitamin K, is safe and reduces preoperative delay and hospital length of stay (LOS).

Methods:

In this pilot study, we reviewed the records of patients admitted to a university-affiliated hospital for hip fracture between Jan. 1, 2012, and Dec. 31, 2016, who were taking VKA. Patients were stratified according to reversal strategy (vitamin K v. PCC). Adverse effects, time to surgery, LOS and mortality were collected from the electronic medical record and were compared between the 2 study groups and a control group not treated with VKA.

Results:

A total of 141 patients were included in the study: 65 in the vitamin K group, 26 in the PCC group and 50 in the control group. The median preoperative delay in the PCC group (20 h [interquartile range (IQR)] 13–25 h]) and the control group (20 h [IQR 15–33 h]) was lower than that in the vitamin K group (45 h [IQR 31–52 h]) (p < 0.001). Patients in the PCC group had a shorter median hospital LOS than those in the vitamin K group (6 d [IQR 4–9 d] v. 8 d [IQR 6–11 d], p < 0.05). No difference was observed in the proportion of patients who received a red blood cell transfusion, or had thrombotic or hemorrhagic complications. No difference in mortality at 12 months was observed between the groups.

Conclusion:

In patients with hip fracture, the use of PCCs as compared to vitamin K to reverse the effect of VKA significantly reduced preoperative delay and hospital LOS, and was not associated with an increase in the rates of thrombotic or hemorrhagic complications. Prospective studies involving a greater number of patients are required to confirm these promising results.

Biomechanical analysis of practitioner's gesture for peripheral venous catheter insertion

Peripheral venous catheter insertion (PVCI) is one of the most common procedures performed by healthcare professionals but remains technically difficult. To develop new medical simulators with better representativeness of the human forearm, an experimental study was performed to collect data related to the puncturing of human skin and a vein in the antebrachial area. A total of 31 volunteers participated in this study. Force sensors and digital image correlation were used to measure the force during the palpation and puncturing of the vein and to retrieve the kinematics of the practitioner's gesture. The in vivo skin rupture load, vein rupture load, and friction loads for skin only and for both the skin and vein were (mean ± standard deviation) 0.85 ± 0.34 N, 1.25 ± 0.37 N, -0.49 ± 0.19 N, and -0.51 ± 0.16 N, respectively. The results of this study can be used to develop realistic skin and vein substitutes and mechanically assess them by reproducing the practitioner's gesture in a controlled fashion.

Extended Trochanteric Osteotomy in Revision Total Hip Arthroplasty: Contemporary Outcomes of 612 Hips

BACKGROUND

Extended trochanteric osteotomies (ETOs) provide wide femoral and acetabular exposure, give direct access to the femoral medullary canal, and facilitate implant removal and new implant placement during selected revision total hip arthroplasties (THAs). Previous studies are limited by modest patient numbers and limited length of follow-up. The goals of the current study were to assess the union rate, complications, and outcomes of contemporary ETOs performed during revision THAs.

METHODS

From 2003 to 2013, 612 ETOs were performed during revision THAs at 1 institution using 2 techniques: Paprosky (laterally based osteotomy; n = 367) and Wagner (anteriorly based osteotomy; n = 245). The indications for the revision procedures were aseptic loosening (65%), periprosthetic joint infection (18%), periprosthetic fracture (6%), femoral implant fracture (5%), and other (6%). The mean patient age was 69 years, and 57% of the patients were male. The mean number of previous THAs was 1.6. The median duration of follow-up was 5 years (range, 2 to 13 years).

RESULTS

The mean Harris hip scores increased from 57 preoperatively to 77 at the latest follow-up (p < 0.001). Radiographic and clinical union was achieved in 98% of the patients at a mean of 6 months (range, 1 to 24 months). The mean migration of the proximal trochanteric osteotomy fragment prior to union was 3 mm (range, 0 to 29 mm). ETO fragment migration of >1 cm occurred in 7% (37) of the 501 hips that had radiographic analysis. Nine hips (2%) had nonunion of the ETO. Intraoperative fracture of the ETO diaphyseal fragment occurred in 22 hips (4%), postoperative fracture of the ETO diaphyseal fragment occurred in 3 hips (0.5%), and postoperative fracture of the greater trochanter occurred in 41 hips (7%). Survivorship at 10 years free of revision for aseptic femoral loosening, free of femoral or acetabular component removal or revision for any reason, and free of reoperation for any reason was 97%, 91%, and 82%, respectively.

CONCLUSIONS

This large series of ETOs shows that the union rate is high and clinically important trochanteric migration is infrequent. The most common complications are fracture of the osteotomy fragment intraoperatively or postoperatively.

LEVEL OF EVIDENCE

Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Effectiveness and Safety of the Combined Use of Tranexamic Acid: A Comparative Observational Study of 1909 Cases

BACKGROUND

Tranexamic acid (TA) use in lower‑limb arthroplasty has been valued in these surgeries high‑risk hemorrhagic due to its antifibrinolytic action. The objective of the present study was to determine the effectiveness of the combined intravenous (IV) and intraarticular (IA) administration of TA in lower‑limb arthroplasty.

METHODS

We conduct a prospective observational study between January 1, 2014, and December 31, 2017, including all programmed lower‑limb arthroplasties. Patients were divided into four groups: no TA, 15 mg/kg IV TA, 3 g IA TA, and 15 mg/kg IV and 3 g IA. The effect on calculated total blood loss (milliliter of red blood cell [RBC]), hemoglobin, transfusion, and duration of hospitalization was studied after adjustment on age, American Society of Anesthesiologists, surgery, and postoperative curative anticoagulation. Complications related to TA administration were systematically reported.

RESULTS

A total of 1909 patients were included - "no TA," n = 184; "IV," n = 1137; "IA," n = 214; and "IV + IA," n = 374. In the IV + IA group, a decrease in blood loss was observed compared to the no TA group (+ 220 ml 95% confidence interval [CI] [184; 255] of RBC P < 0.001) and in the IA group (+ 65 ml 95% CI [30; 99] of RBC P < 0.001). The length of hospital stay of the IV + IA group was shorter compared to the no TA group (hazard ratio [HR] 0.35, 95% CI [0.29; 0.43], P < 0.001) to the IA group (HR 0.57, 95% CI [0.48; 0.69], P < 0.001) and the IV group (HR 0.45, 95% CI [0.39; 0.50], P < 0.001). One case of deep vein thrombosis occurred in the group without TA.

CONCLUSION

Administration of combined TA appears effective and safe; further studies are needed in order to establish a consensual protocol.

Strain Assessment of Deep Fascia of the Thigh During Leg Movement: An in situ Study

Fascia is a fibrous connective tissue present all over the body. At the lower limb level, the deep fascia that is overlying muscles of the outer thigh and sheathing them (fascia lata) is involved in various pathologies. However, the understanding and quantification of the mechanisms involved in these sheathing effects are still unclear. The aim of this study is to observe and quantify the strain field of the fascia lata, including the iliotibial tract (ITT), during a passive movement of the knee. Three fresh postmortem human subjects were studied. To measure hip and knee angles during knee flexion-extension, passive movements from 0° to around 120° were recorded with a motion analysis system and strain fields of the fascia were acquired using digital image correlation. Strains were computed for three areas of the fascia lata: anterior fascia, lateral fascia, and ITT. Mean principal strains showed different strain mechanisms depending on location on the fascia and knee angle. For the ITT, two strain mechanisms were observed depending on knee movement: compression is observed when the knee is extended relative to the reference position of 47°, however, tension and pure shear can be observed when the knee is flexed. For the anterior and lateral fascia, in most cases, minor strain is higher than major strain in absolute value, suggesting high tissue compression probably due to microstructural fiber rearrangements. This in situ study is the first attempt to quantify the superficial strain field of fascia lata during passive leg movement. The study presents some limitations but provides a step in understanding strain mechanism of the fascia lata during passive knee movement.

Ilio-psoas impingement with a dual-mobility liner: an original case report and review of literature

Ilio-psoas impingement after total hip arthroplasty often occurs with the metallic rim of the acetabular cup. The main causes are poor cup anteversion or anterior wall defect. We firstly report here the case of a patient complaining of iliopsoas impingement due to contact with the liner of a dual-mobility device. Ultrasonography and Computed Tomographic scan clearly showed the direct mechanical contact of the dual-mobility liner with the iliopsoas tendon.

Quadriceps Snip in 321 Revision Total Knee Arthroplasties: A Safe Technique in a Matched Cohort Study

BACKGROUND

Quadriceps snips (QSs) are commonly used to gain enhanced exposure during revision total knee arthroplasties (TKAs). The goals of this study were to evaluate the longer-term clinical outcomes and complications in a contemporary cohort of patients treated with QS and to compare them to a matched cohort treated with standard exposure during revision TKAs.

METHODS

We retrospectively identified 3107 revision TKAs performed at our institution between 2002 and 2012. QS was performed in 321 of these knees. Each QS revision TKA was 1:1 matched to a control (standard exposure) based on age, gender, body mass index, surgery date, and reason for revision. Clinical outcomes studied included Knee Society Score, range of motion, and extensor lag. Other outcomes assessed were complications (especially extensor mechanism disruption) and survivorship. Mean follow-up was 5 years.

RESULTS

The mean Knee Society Score improvement was not significantly different between groups (P = .9). At latest follow-up, the mean range of motion was 93° in the QS group and was slightly higher at 100° in the control group (P = .002). Postoperative extensor lag of 10 degrees or more was present in 21 (6.7%) QS knees versus 19 (6.8%) control knees (P = .95). Complication rates were similar in both groups with extensor mechanism disruption occurring in 3 in the QS group (0.7% at 10 years) versus 4 in the control group (0.8% at 10 years; P = .91). Kaplan-Meier survivorships free of revision for aseptic loosening, free of any revision, and free of any reoperation were similar at 10 years (85%, 71%, and 61%, respectively, in the QS group vs 89%, 70% and 60%, respectively, in the control group).

CONCLUSION

This matched cohort study is the largest to report the results of QS and also the largest to report results compared with patients treated with standard exposure. Building on the results of smaller historical series, this study demonstrates QS was a facile technique in complex revision TKAs allowing for safe exposure with few complications.

LEVEL OF EVIDENCE

III (case-control study).

A Drug Eluting Scaffold for the Treatment of Arthrofibrosis

INTRODUCTION

The inflammatory cascade and production of prostaglandins may play a role in the pathogenesis of arthrofibrosis, a debilitating condition after joint replacement and other orthopedic procedures. Cyclooxygenase 2 (COX-2) inhibitors may mitigate the inflammatory response and formation of arthrofibrosis, but oral delivery is associated with risk of systemic side effects in many patients. The nonsteroidal anti-inflammatory drug, celecoxib, may have therapeutic benefits for arthrofibrosis, but current methods for its local delivery (e.g., biologically derived microspheres) are not translatable to immediate clinical use. Therefore, we investigated the use of a drug scaffold for sustainable intra-articular delivery of therapeutic doses of celecoxib.

MATERIALS AND METHODS

Celecoxib was eluted from clinically approved biodegradable collagen membranes over 7 days as measured by UV spectroscopy and high-performance liquid chromatography/mass spectroscopy. Eluted concentrations of celecoxib were examined for toxicity (live/dead staining) and profibrotic gene expression (real-time-quantitative polymerase chain reaction) in rabbit knee capsular fibroblasts in vitro.

RESULTS

Sustained concentrations of celecoxib eluted from the membrane over 7 days from both a wet and dry scaffold, with a burst release (30-45%) of celecoxib in the first 2 h. Rabbit cells treated with eluted concentrations experienced a toxic response to the burst release doses, and inhibitory effects on profibrotic genes were seen in response to the sustained doses eluted from the scaffold.

CONCLUSIONS

This study characterized the novel use of collagen scaffolds for intra-articular drug delivery to treat arthrofibrosis. Scaffolds exhibit celecoxib release through an initial burst release followed by sustained release of antifibrotic doses over 7 days. Thus, collagen scaffolds are promising for clinician-directed treatment of arthrofibrosis.

Bone cement usage modalities at a multi-site university hospital centre

BACKGROUND

Although cements are widely used during arthroplasty procedures, few recommendations exist regarding their optimal usage modalities, which, nevertheless, govern the long-term surgical outcomes. No detailed information is available on how cements are used in French hospitals. The objectives of this questionnaire survey among surgeons working at a multi-site university hospital in France were to describe practices, determine whether these varied with surgeon experience, and look for differences compared to recommendations.

HYPOTHESIS

Cementing techniques vary widely among surgeons at a university hospital.

MATERIAL AND METHODS

A questionnaire was sent to the five orthopaedic departments of our university hospital to collect data on the surgeons (age, sex, years of experience), their practice (type of implants used, annual number of arthroplasties with each arthroplasty type and each indication, and proportion of cemented arthroplasties), the type of cement used, and the cementing technique.

RESULTS

Of the 34 surgeons, 21 completed the questionnaire, 20 males and 1 female with a mean age of 41 years (range, 31-59 years) and a mean of 11 years (range, 1-29 years) of experience. High-viscosity antibiotic-loaded cement was preferred by 20 (95%) surgeons, notably for knee arthroplasties, of which the median annual numbers were 55 (range, 0-218) and 8 (range, 1-40) for primary and revision cemented procedures, respectively. Various cementing techniques in ambient air were used: 12/21 (57%) surgeons used pulsed lavage to prepare the bone before cementation and 18/21 (86%) applied the cement to both the bone cuts and the implant. Of the 18 surgeons who performed knee arthroplasties, 12 used pulsed lavage, including 9 of the 11 surgeons with more than 5 years of experience and only 3 of the 7 less experienced surgeons. Similarly, of the 12 surgeons who used pulsed lavage for cemented arthroplasties, 11 were among the 12 surgeons who performed more than 15 cemented arthroplasties annually and 1 was among the 6 who performed fewer cemented arthroplasties.

DISCUSSION

Cementing techniques varied widely, reflecting the dearth of recommendations and controversial results of published studies. In our centre, the use of pulsed lavage to improve bone preparation and cement application to both the bone and the implant should be promoted, as both techniques are universally advocated. Our study demonstrates the need to provide surgeons with opportunities to exchange their experiences about the other aspects of cementing in order to harmonise practices and to optimise the use of cement.

LEVEL OF EVIDENCE

IV, questionnaire survey.

Axial patellar engagement index and patellar tilt after medial patello-femoral ligament reconstruction in children and adolescents

BACKGROUND

The medial patello-femoral ligament (MPFL) is a major patellar stabiliser whose reconstruction in adults involves graft fixation within a femoral tunnel. In skeletally immature patients, in contrast, the graft is fixed to the soft tissues to allow normal growth. The primary objective of this prospective study was to perform computed tomography (CT) and magnetic resonance imaging (MRI) assessments of medium-term correction of patellar tilt and of the axial patellar engagement index (AEI) after a paediatric variant of MPFL reconstruction in skeletally immature patients.

HYPOTHESIS

MPFL reconstruction, performed alone or combined with other procedures in skeletally immature patients, decreases patellar tilt and improves the AEI.

MATERIAL AND METHODS

Eighteen children and adolescents with a median age of 14.6 years (range, 8-17 years) who underwent MPFL reconstruction on 20 knees were included in this prospective observational study. A double-strand gracilis tendon graft passed through the medial collateral ligament was used. MPFL reconstruction was performed alone in 13 knees and was combined with lateral retinaculum release, tibial tuberosity translation, and/or trochleoplasty in 7 knees. Patellar tilt and AEI values determined on preoperative and post-operative imaging studies with the quadriceps relaxed and contracted were compared. A physical examination was also performed.

RESULTS

From baseline to last follow-up after a mean of 43 months (range, 24-63 months), patellar tilt decreased from 20° preoperatively to 9° with the quadriceps relaxed and from 33° to 15.4° with the quadriceps contracted. The AEI increased from 0.78 at baseline to 0.93 at last follow-up. No dislocation or subluxation recurrences were recorded during follow-up.

DISCUSSION

The patellar tilt and AEI improvements seen after paediatric MPFL reconstruction confirm the study hypothesis. This is the first prospective study of patellar position in the axial plane as assessed by CT and MRI after paediatric MPFL reconstruction. In everyday clinical practice, 3D assessments of patellar tilt and the AEI should be performed to evaluate correction of the abnormalities.

LEVEL OF EVIDENCE

II, non-randomised prospective observational study.

Effectiveness and Safety of the Combined Use of Tranexamic Acid: A Comparative Observational Study of 1909 Cases

BACKGROUND

Tranexamic acid (TA) use in lower-limb arthroplasty has been valued in these surgeries high-risk hemorrhagic due to its antifibrinolytic action. The objective of the present study was to determine the effectiveness of the combined intravenous (IV) and intraarticular (IA) administration of TA in lower-limb arthroplasty.

METHODS

We conduct a prospective observational study between January 1, 2014, and December 31, 2017, including all programmed lower-limb arthroplasties. Patients were divided into four groups: no TA, 15 mg/kg IV TA, 3 g IA TA, and 15 mg/kg IV and 3 g IA. The effect on calculated total blood loss (milliliter of red blood cell [RBC]), hemoglobin, transfusion, and duration of hospitalization was studied after adjustment on age, American Society of Anesthesiologists, surgery, and postoperative curative anticoagulation. Complications related to TA administration were systematically reported.

RESULTS

A total of 1909 patients were included - "no TA," n = 184; "IV," n = 1137; "IA," n = 214; and "IV + IA," n = 374. In the IV + IA group, a decrease in blood loss was observed compared to the no TA group (+220 ml 95% confidence interval [CI] [184; 255] of RBC P < 0.001) and in the IA group (+65 ml 95% CI [30; 99] of RBC P < 0.001). The length of hospital stay of the IV + IA group was shorter compared to the no TA group (hazard ratio [HR] 0.35, 95% CI [0.29; 0.43], P < 0.001) to the IA group (HR 0.57, 95% CI [0.48; 0.69], P < 0.001) and the IV group (HR 0.45, 95% CI [0.39; 0.50], P < 0.001). One case of deep vein thrombosis occurred in the group without TA.

CONCLUSION

Administration of combined TA appears effective and safe; further studies are needed in order to establish a consensual protocol.

Short-term outcomes after elective colon cancer surgery: an observational study from the Norwegian registry for gastrointestinal and HPB surgery, NoRGast

BACKGROUND

To describe the real burden of major complications after elective surgery for colon cancer in Norway, and to assess which predictors that are significantly associated with the short-term outcome.

METHODS

An observational, multi-centre analysis of prospectively registered colon resections registered into the Norwegian Registry for Gastrointestinal Surgery, NoRGast, between January 2014 and December 2016. A propensity score-adjusted subgroup analysis for surgical access groups was attempted, with laparoscopic resections grouped as intention-to-treat.

RESULTS

Out of 1812 resections, 14.0% of patients experienced a major complication within 30 days following surgery. The over-all reoperation rate was 8.7%, and rate of reoperation for anastomotic leak was 3.8%. Twenty patients (1.1%) died within 30 days after surgery. Higher age was not a significant predictor of major complications, including 30-day mortality. After correction for all co-variables, open access surgery was associated with higher rates of major complications (OR 1.67 (CI 1.22-2.29), p = 0.002), higher 30-day mortality (OR 4.39 (CI 1.19-16.13) p = 0.026) and longer length-of-stay (HR 0.58 (CI 0.52-0.65) p < 0.001).

CONCLUSIONS

Our results indicate a low complication burden and high rate of uneventful patient journeys after elective surgery for colon cancer in Norway. Age was not associated with higher morbidity or mortality rates. Open access surgery was associated with an inferior short-term outcome.

Joint contracture is reduced by intra-articular implantation of rosiglitazone-loaded hydrogels in a rabbit model of arthrofibrosis

Trauma, surgery, and other inflammatory conditions can lead to debilitating joint contractures. Adjunct pharmacologic modalities may permit clinical prevention and treatment of recalcitrant joint contractures. We investigated the therapeutic potential of rosiglitazone by intra-articular delivery via oligo[poly(ethylene glycol)fumarate] (OPF) hydrogels in an established rabbit model of arthrofibrosis. OPF hydrogels loaded with rosiglitazone were characterized for drug elution properties upon soaking in minimum essential media (MEM) with 10% fetal bovine serum and measurements of drug concentrations via High Performance Liquid Chromatography (HPLC). Drug-loaded scaffolds were surgically implanted into 24 skeletally mature female New Zealand White rabbits that were divided into equal groups receiving OPF hydrogels loaded with rosiglitazone (1.67 mg), or vehicle control (10 µl DMSO). After 8 weeks of joint immobilization, rabbits were allowed unrestricted cage activity for 16 weeks. Contracture angles of rabbit limbs treated with rosiglitazone showed statistically significant improvements in flexion compared to control animals (mean angles, respectively, 64.4° vs. 53.3°, p < 0.03). At time of sacrifice (week 24), animals in the rosiglitazone group continued to exhibit less joint contracture than controls (119.0° vs. 99.5°, p = 0.014). The intra-articular delivery of rosiglitazone using implanted OPF hydrogels decreases flexion contractures in a rabbit model of arthrofibrosis without causing adverse effects (e.g., gross inflammation or arthritis). Statement of Clinical Significance: Post-traumatic joint contractures are common and debilitating, with limited available treatment options. Pharmacologic interventions can potentially prevent and treat such contractures. This study is translational in that a commercially approved medication has been repurposed through a novel delivery device. © 2018 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 36:2949-2955, 2018.

Anatomy of the Right Anterior Sector of the Liver and Its Clinical Implications in Surgery

BACKGROUND

Surgery remains the gold standard both for delimited hepatocellular carcinoma by selective anatomic liver segentectomy and for colorectal liver metastases by parenchymal sparing liver resection. Right anterior sector (RAS) (segments V-VIII; Couinaud) is the largest and most difficult sector to operate on. A better knowledge of its segmentation could prevent postoperative remnant liver ischemia and its impacts on patient's survival.

METHODS

A literature search was conducted in PubMed for papers on anatomy and surgery of the right anterior sector.

RESULTS

Segmentation of the RAS depended of the anatomic variations of the third-order portal branches. Cranio-caudal segmentation was the most commonly found (50-53%), followed by ventro-dorsal (23-26%), trifurcation (13-20%), and quadrifurcation types (5-11%). Ventral and dorsal partial or total subsegmentectomy seemed accessible in 47 to 50% of patients, including bifurcation, trifurcation, and quadrifurcation types, and could spare up to 22% of the total liver volume. The RAS hepatic vein was present in 85-100% of the patients and could be used as a landmark between RAS dorsal and ventral part in 63% of patients. Reported overall morbidity rate of RAS subsegmentectomy ranged from 33 to 59% among studies with a postoperative major complication rate (Clavien-Dindo ≥ III) ranging around 18% and a biliary leakage rate from 16 to 21%. In-hospital reported mortality rate was low (0-3%), and results were comparable to "classic" liver resections. RAS subsegmentectomy remains a complex procedure; median operating time ranged from 253 to 520 min and median intraoperative blood loss reached 1255 ml.

CONCLUSION

Better knowledge of RAS anatomy could allow for parenchymal preservation by using subsegmentectomy of the RAS, selective or as a part of a major hepatectomy.

The New National Registry for Gastrointestinal Surgery in Norway: NoRGast

Background and Aims:

There is an increasing demand for high-quality data for the outcome of health care. Diseases of the gastro-intestinal tract involve large patient groups often presenting with serious or life-threatening conditions. Complications may affect treatment outcomes and lead to increased mortality or reduced quality of life. A continuous, risk-adjusted monitoring of major complications is important to improve the quality of health care to patients undergoing gastrointestinal resections. We present the development of the Norwegian Registry for Gastrointestinal Surgery, a national registry for colorectal, upper gastrointestinal, and hepato-pancreato-biliary resections in Norway.

Materials and Methods:

A narrative and qualitative presentation of the development and current state of the registry.

Results:

We present the variables and the analysis tools and provide examples for the potential in quality improvement and research. Core characteristics include a strictly limited set of variables to reflect important risk factors, the procedure performed, and the clinical outcomes.

Conclusion:

A registry with the potential to present complete national cohort data is a powerful tool for quality improvement and research.

Navigated retrograde endoscopic myotomy (REM) for the treatment of therapy-resistant achalasia

BACKGROUND

In achalasia, muscle spasm may involve the proximal esophagus. When the muscle spasm is located in the proximal esophagus, conventional per oral endoscopic myotomy (POEM) may not be sufficient to relieve symptoms. In this paper, we describe retrograde endoscopic myotomy (REM) as a novel approach to perform myotomy of the proximal esophagus, with the application of a navigation tool for anatomical guidance during REM. We aim to evaluate the feasibility and safety of REM and usefulness of the navigation during REM.

METHOD

A 42-year-old male with type III achalasia who was treated with laparoscopic myotomy with fundoplication, multiple pneumatic balloon dilations, Botox injections and anterior POEM of the middle and distal esophagus without symptomatic effect. Repeated high-resolution- manometry (HRM) revealed occluding contractions of high amplitude around and above the aortic arch. A probe-based real-time electromagnetic navigation platform was used to facilitate real-time anatomical orientation and to evaluate myotomy position and length during REM.

RESULTS

The navigation system aided in identifying the major structures of the mediastinum, and position and length of the myotomy. Twelve weeks after REM, the Eckardt score fell from seven at baseline seven to two. We also observed improvement with reduction of the pressure at the level of previous spasms in the proximal esophagus from 124 mmHg to 8 mmHg on HRM.

CONCLUSION

REM makes the proximal esophagus accessible for endoscopic myotomy. Potential indication for REM is motility disorders in the proximal esophagus and therapy failure after POEM.

Prior Knee Arthroscopy Does Not Influence Long-Term Total Knee Arthroplasty Outcomes and Survivorship

BACKGROUND

Arthroscopic knee surgery frequently precedes total knee arthroplasty (TKA). There have been mixed data on the effect of prior arthroscopic surgery on results of TKA. The purpose of this study was to compare the 10-year Knee Society Score (KSS), survivorship, and complications of TKA in a cohort of patients who had a previous knee arthroscopy to a control cohort.

METHODS

A retrospective review of 1315 TKAs who underwent a primary TKA between 2003 and 2004 was performed. Of these, 160 TKAs had previous arthroscopy (excluding ligamentous reconstruction). A matched cohort study 2:1 was carried out with a group of 320 controls (no prior surgery). Outcomes were assessed with the original KSS, range-of-motion, complications, and survivorships. Mean follow-up was 9 years.

RESULTS

The mean KSS increased from 36-84 in the arthroscopy group vs 35-86 in the control group (P = .5). The mean preoperative and postoperative range-of-motion was not different between groups (P = .2). The survivorship free of complication at 5 years was similar in both groups (94.3% in arthroscopy group vs. 95.3% in the control; P = .7) with infection in 2 controls and 3 arthroscopy cases (P = .2). The survivorships free of revision for aseptic loosening, revision for any reason, and reoperation were similar at 10 years (96.5%, 94.6%, and 89.2%, respectively, in the arthroscopy group vs 96.2%, 95.9%, and 91.5% in the control group).

CONCLUSION

There were no significant differences between both groups. These data are reassuring and valuable in an era in which many candidates for TKA will have had previous arthroscopic knee surgery.

Molecular pathology of total knee arthroplasty instability defined by RNA-seq

Total knee arthroplasty (TKA) is a durable and reliable procedure to alleviate pain and improve joint function. However, failures related to flexion instability sometimes occur. The goal of this study was to define biological differences between tissues from patients with and without flexion instability of the knee after TKA. Human knee joint capsule tissues were collected at the time of primary or revision TKAs and analyzed by RT-qPCR and RNA-seq, revealing novel patterns of differential gene expression between the two groups. Interestingly, genes related to collagen production and extracellular matrix (ECM) degradation were higher in samples from patients with flexion instability. Partitioned clustering analyses further emphasized differential gene expression patterns between sample types that may help guide clinical interpretations of this complication. Future efforts to disentangle the effects of physical and biological (e.g., transcriptomic modifications) risk factors will aid in further characterizing and avoiding flexion instability after TKA.

Long-term survivorship of the Corail™ standard stem

INTRODUCTION

The Corail™ stem, which was first introduced in 1986, has since been modified twice: first to make the neck thinner and then to change the location of the laser markings. The survival and complications of the first-generation straight, titanium, hydroxyapatite-coated stem are known; however, there is little specific information about the latest-generation stem. This led us to conduct a retrospective study to determine the: (1) long-term survival; (2) clinical and radiographic outcomes; (3) complications; and (4) risk factors for revision of the newest Corail™ stem.

HYPOTHESIS

The newest Corail™ AMT (Articul/EZE™ Mini Taper) standard stem has comparable survival to prior models.

PATIENTS AND METHODS

This single-center, retrospective study included 133 patients (140 hips), who underwent primary total hip arthroplasty (THA), between January and December 2004, in which a Corail™ Standard stem was implanted using a posterolateral approach. Patients who underwent revision THA, THA due to femoral neck fracture or who received lateralized (offset) stems were excluded. The mean age at the time of THA was 69±13 years [35-92] in 85 men (61%) and 55 women (39%) who had a mean BMI of 27kg/m²±11 [16-39]. At the latest follow-up, 32 patients (32 hips) had died and 8 patients (8 hips) had less than 3 years' follow-up, thus were not included in the clinical evaluation. The Merle d'Aubigné (PMA) score was collected. The stem's survivorship was calculated using the Kaplan-Meier method with revision for aseptic loosening and revision or implant removal for any reason as the end-points. The Cox model was used to analyze risk factors for revision. The mean follow-up was 10±3 years [3-12].

RESULTS

The PMA score was 12±2.6 [5-17] preoperatively and 16±2.7 [7-18] at the last follow-up (P<0.00001). Eighteen complications (12.8%) were recorded at the last follow-up. There were 15 early complications: 6 dislocations, 5 calcar fractures (4 treated by wire cerclage and 1 by stem change plus wire cerclage), 2 greater trochanter fractures (treated non-surgically) and 2 cases of sciatic nerve palsy. There were 3 late complications: 2 cases of iliopsoas irritation and 1 ceramic insert fracture. Stem survival for surgical revision due to aseptic loosening was 98% (95% CI: [0.96-1]). At 12 years, 95% of stems had not been revised or removed (95% CI: [0.92-0.99]). Being less than 58 years of age at the time of surgery was the only risk factor significantly associated with stem revision for any reason (P=0.04).

CONCLUSION

Survival of the Corail™ Standard stem is similar to that of previous generation stems. The changes made in this stem solved the neck failure problem and did not induce new complications.

LEVEL OF EVIDENCE

Level IV (retrospective study).

What are the risk factors for dislocation in primary total hip arthroplasty? A multicenter case-control study of 128 unstable and 438 stable hips

INTRODUCTION

Dislocation after total hip arthroplasty (THA) is a leading reason for surgical revision. The risk factors for dislocation are controversial, particularly those related to the patient and to the surgical procedure itself. The differences in opinion on the impact of these factors stem from the fact they are often evaluated using retrospective studies or in limited patient populations. This led us to carry out a prospective case-control study on a large population to determine: 1) the risk factors for dislocation after THA, 2) the features of these dislocations, and 3) the contribution of patient-related factors and surgery-related factors.

HYPOTHESIS

Risk factors for dislocation related to the patient and procedure can be identified using a large case-control study.

PATIENTS AND METHODS

A multicenter, prospective case-control study was performed between January 1 and December 31, 2013. Four patients with stable THAs were matched to each patient with a dislocated THA. This led to 566 primary THA cases being included: 128 unstable, 438 stable. The primary matching factors were sex, age, initial diagnosis, surgical approach, implantation date and type of implants (bearing size, standard or dual-mobility cup).

RESULTS

The patients with unstable THAs were 67±12 [37-73]years old on average; there were 61 women (48%) and 67 men (52%). Hip osteoarthritis (OA) was the main reason for the THA procedure in 71% (91/128) of the unstable group. The dislocation was posterior in 84 cases and anterior in 44 cases. The dislocation occurred within 3 months of the primary surgery in 48 cases (38%), 3 to 12 months after in 23 cases (18%), 1 to 5years after in 20 cases (16%), 5 to 10years after in 17 cases (13%) and more than 10years later in 20 cases. The dislocation recurred within 6 months of the initial dislocation in 23 of the 128 cases (18%). The risk factors for instability were a high ASA score with an odds ratio (OR) of 1.93 (95% CI: 1.4-2.6), neurological disability (cognitive, motor or psychiatric disorders) with an OR of 3.9 (95% CI: 2.15-7.1), history of spinal disease (lumbar stenosis, spinal fusion, discectomy, scoliosis and injury sequelae) with an OR of 1.89 (95% CI: 1.0-3.6), unrepaired joint capsule (all approaches) with an OR of 4.1 (95% CI: 2.3-7.37), unrepaired joint capsule (posterior approach) with an OR of 6.0 (95% CI: 2.2-15.9), and cup inclination outside Lewinnek's safe zone (30°-50°) with OR of 2.4 (95% CI: 1.4-4.0).

DISCUSSION

This large comparative study isolated important patient-related factors for dislocation that surgeons must be aware of. We also found evidence that implanting the cup in 30° to 50° inclination has a major impact on preventing dislocation.

LEVEL OF EVIDENCE

Level III; case-control study.

Seasonality of Periprosthetic Femur Fractures in 12,700 Primary and Revision Total Hip Arthroplasties

BACKGROUND

Periprosthetic femur fractures after primary and revision total hip arthroplasty (THA) are one of the most common long-term reasons for reoperation after THA. Previous investigations have analyzed the incidence and risk factors of these fractures. No previous study, however, has analyzed a variation in periprosthetic femur fractures between meteorologic seasons. The aim of this study was to compare the incidence of periprosthetic femur fractures after primary and revision THAs depending on the meteorologic season.

METHODS

We identified 8920 patients (10,672 hips) who underwent primary THAs and 1830 patients (1998 hips) who underwent revision THAs at our institution between 1995 and 2011. All patients resided in the Upper Midwest at the time of surgery. Patients who experienced periprosthetic femur fractures were identified and categorized based on the meteorologic season. A Cox model was used to assess the association of seasonality with the risk of fracture.

RESULTS

During the study period, 165 primary THAs and 80 revision THAs sustained a periprosthetic femur fracture. Using winter as a reference, the risk of a periprosthetic femur fracture after primary THA was not statistically higher in the spring (hazard ratio [HR] = 1.3; P = .2), autumn (HR = 1.4; P = .2), and summer (HR = 1.415; P = .1). Similarly, the risk of periprosthetic femur fracture after revision THA was not statistically higher in the spring (HR = 0.9; P = .6), autumn (HR = 0.6; P = .1), and summer (HR = 0.9; P = 1.0).

CONCLUSION

The risk of periprosthetic femur fracture after primary and revision THA does not significantly differ between meteorologic seasons.

Proximal femoral replacement in contemporary revision total hip arthroplasty for severe femoral bone loss

Aims

Loss or absence of proximal femoral bone in revision total hip arthroplasty (THA) remains a significant challenge. While the main indication for the use of proximal femoral replacements (PFRs) is in the treatment of malignant disease, they have a valuable role in revision THA for loosening, fracture and infection in patients with bone loss. Our aim was to determine the clinical outcomes, implant survivorship, and complications of PFRs used in revision THA for indications other than malignancy.

Patients and Methods

A retrospective review of 44 patients who underwent revision THA using a PFR between 2000 and 2013 was undertaken. Their mean age was 79 years (53 to 97); 31 (70%) were women. The bone loss was classified as Paprosky IIIB or IV in all patients. The mean follow-up was six years (2 to 12), at which time 22 patients had died and five were lost to follow-up.

Results

The mean Harris Hip Score improved from 42.8 (25.9 to 82.9) pre-operatively to 68.5 (21.0 to 87.7) post-operatively (p = 0.0009). A total of two PFRs had been revised, one for periprosthetic infection eight years post-operatively and one for aseptic loosening six years post-operatively. The Kaplan-Meier survivorship free of any revision or removal of an implant was 86% at five years and 66% years at ten years. A total of 12 patients (27%) had a complication including six with a dislocation.

Conclusion

PFRs provide a useful salvage option for patients, particularly the elderly with massive proximal femoral bone loss who require revision THA, with significant clinical improvement. While the survivorship of the implant is good at five years, dislocation continues to be the most common complication. The judicious use of larger femoral heads, dual-mobility constructs, or constrained liners may help to minimise the risk of dislocation. Cite this article: Bone Joint J 2017;99-B:325–9.

Population-based study on resection rates and survival in patients with colorectal liver metastasis in Norway

Background

Detailed knowledge about the proportion of patients with colorectal liver metastases (CLM) undergoing resection is sparse. The aim of this study was to analyse cumulative resection rates and survival in patients with CLM.

Methods

For this population-based study of patients developing CLM during 2011–2013, data were extracted from the Norwegian Patient Registry and the Cancer Registry of Norway.

Results

A total of 2960 patients had CLM; their median overall survival was 10·9 months. Liver resection was performed in 538 patients. The cumulative resection rate was 20·0 per cent. The cumulative resection rate was 23·3 per cent in patients aged less than 40 years, 31·1 per cent in patients aged 40–59 years, 24·7 per cent in those aged 60–74 years, 17·9 per cent in those aged 75–79 years and 4·7 per cent in patients aged 80 years or more (P &lt; 0·001). In multivariable analysis, resection rate was associated with age, extrahepatic metastases, disease-free interval and geographical region. Overall survival after diagnosis of CLM was affected by liver resection (hazard ratio (HR) 0·54, 95 per cent c.i. 0·34 to 0·86), rectal cancer (HR 0·82, 0·74 to 0·90), metachronous disease (HR 0·66, 0·60 to 0·74), increasing age (HR 1·32, 1·28 to 1·37), region, and extrahepatic metastases (HR 1·90, 1·74 to 2·07). Three- and 4-year overall survival rates after hepatectomy were 73·2 and 54·8 per cent respectively.

Conclusion

The cumulative resection rate in patients with CLM in Norway between 2011 and 2013 was 20 per cent. Resection rates varied across geographical regions, and with patient and disease characteristics.

Epidemiology of Severely and Fatally Injured Patients in Western Part of Norway

Background and Aims:

Analysis of the injury mechanism and characteristics of severely and fatally injured patients in the western part of Norway.

Material and Methods:

We did a prospective registration of all severely injured patients hospitalized during a three-year period. The files of severely injured patients that died at scene or during transport were retrospectively retrieved from the Forensic Department. A total of 558 patients with an Injury Severity Score > 15 were included.

Results:

Four-hundred-forty-four men (79.6 %) and 114 women (20.4 %) with a median age of 36 and 51.5 years respectively were included. The proportion of female patients older than 80 years were 19.3 % compared to 5.6 % for men. A total of 215 (38.5 %) patients died and 149 (69.3 %) of these patients died on scene or during transport. The incidence of severely injured patients in Hordaland County was 30 per 100 000 inhabitants per year. The incidence was lowest among children below 5 years (7/100 000/year) and highest among persons older than 80 years (95/100 000/year). Men had a 3.8 times greater risk of getting seriously injured compared to women. Road traffic accidents were the cause of the injuries in 235 (42.1%) patients and 35.8% of these patients died. A total of 215 (38.5 %) patients were injured due to falls and 30.2 % of these patients died. Patients who had sustained falls were significantly older than patents with other injury mechanisms (p < 0.001, CI = 13.0–20.2). The proportion of patients with penetrating injuries was 7.3 %.

Conclusion:

The incidence of severely injured patients was 30/100000/year. Men and elderly people had a higher risk of getting severely injured. Falls were the dominating injury mechanism among elderly.

Acute Pancreatitis in Bergen, Norway

Background:

Studies on the incidence and etiology of acute pancreatitis show large regional differences. This study was performed to establish incidence, etiology and severity of acute pancreatitis in the population of Bergen, Norway.

Methods:

A study of all patients with acute pancreatitis admitted to Haukeland University Hospital over a 10-year period was performed. Information was obtained about the number of patients with acute pancreatitis admitted to the Deaconess Hospital in Bergen.

Results:

A total of 978 admissions of acute pancreatitis were recorded in these two hospitals giving an incidence of 30.6 per 100 000. Haukeland University Hospital had 757 admissions of acute pancreatitis in 487 patients. Pancreatitis was severe in 20 % (96/ 487) of patients, more often in males (25 %) than in females (14 %). Mortality due to acute pancreatitis was 3 % (16/487). Gallstones were found to be an etiological factor in 48.5 % and alcohol consumption in 19 % of patients. The risk of recurrent pancreatitis was 47 % in alcohol induced and 17 % in gallstone induced pancreatitis. The last five years of the study period, endoscopic sphincterotomy of patients with gallstone pancreatitis, resulted in drop in relapse rate from 33 % to 1.6 %.

Conclusion:

The incidence of acute pancreatitis was found to be 30.6 per 100 000 with 48.5 % associated with gallstones and 17 % alcohol induced. Incidence of first attack was 20/100 000. Pancreatitis was classified as severe in 20 % of cases with a mortality of 3 %.

Carcinoid Tumours in the Gastrointestinal Tract — A Population-Based Study from Western Norway

Objective:

To analyze population-based incidence, anatomic distribution and patient characteristics of gastrointestinal carcinoid tumours.

Background:

Neuroendocrine carcinomas (NE, carcinoid tumours) arise from neuroendocrine cells and are most commonly found in gastrointestinal tract and lungs. Previous studies on carcinoids report varying incidence rates, location of tumours and patient survival rates.

Methods:

Retrospective study.88 patients were diagnosed with carcinoids located in the gastrointestinal tract in the period 1983–2003 in the Norwegian counties Hordaland and Sogn og Fjordane. Patient and tumour characteristics, treatment and survival were analyzed in a sub-group of 51 patients treated at Haukeland University Hospital.

Results:

Incidence of carcinoids was 0.8 when analyzed from the counties Hordaland and Sogn og Fjordane as well as when analyzed from Haukeland University Hospital. There were 26 men and 25 women. Median age at surgery was 61 years (range 17–87 years). The tumours were located in the small bowel in 53%, appendix 18%, colon 4%, rectum 4%, stomach 8% and duodenum 10%. Five-year survival rate was 50% in stomach, 80% in duodenum, 43% in the small bowel, 100% for tumours in appendix, 40% in colon and 100% in rectum.

Conclusion:

Carcinoid tumours are relatively uncommon neoplasms and most of them are found in the small bowel. Carcinoids in the ileum tend to be more aggressive and carry a poorer prognosis than carcinoids at other locations. Tumours in the appendix are found at lower age and in an early stage. They rarely metastasize and have an excellent prognosis.

Cementless Corail™ femoral stems with laser neck etching: Long-term survival, rupture rate and risk factors in 295 stems

INTRODUCTION

Implant neck fracture involving a non-modular femoral stem is rare in primary total hip arthroplasty (THA). Occasional cases have been reported following laser etching of the Corail(tm) stem, but risk factors have not been precisely determined. We therefore performed a retrospective study on a series of Corail(tm) stems with laser neck etching, in order to: (1) determine the exact implant neck fracture rate at 10 years, and (2) identify associated risk factors.

HYPOTHESIS

Laser etching increases the rate of implant neck fracture.

MATERIALS AND METHODS

Between October 2002 and December 2003, 295 THAs were consecutively performed using the Corail(tm) stem with laser neck etching, in 286 patients: 151 male (53%), 135 female (47%); mean age, 63 years (range, 18-89 years); mean weight, 73kg (range, 45-120kg). Stems were standard in 240 cases (81%) and lateralized in 55 (19%). The main assessment criterion was stem replacement for implant neck fracture.

RESULTS

At a mean 10 years' follow-up (range, 1-11 years), 11 patients were lost to follow-up (4%) and 35 had died (12%) (with stem in situ). Overall 10-year stem survival was 91% (95% CI: [87-94%]). Sixteen patients (5.4%) underwent revision surgery for implant neck fracture, 6 (2%) bone and joint infection and in 4 cases (1.3%) the stem was replaced preventively for fracture risk suspected during a revision procedure on the cup. All fractures were of the fatigue type, implicating implant neck laser etching. Mean time to fracture was 4.5 years (range, 1.4-9.8 years). Risk factors comprised: weight>80kg (P=0.002) (OR=5.7; 95% CI: 1.9-17), age<60 years (P=0.02) (OR=3.4; 95% CI: 1.2-9.6), male gender (P=0.01) (OR=14.8; 95% CI: 1.9-113) and lateralized stem (P<0.001) (OR=6.5, 95% CI: 2.3-18).

CONCLUSION

The present 5.4% fracture rate was higher than in registry data (<1%). Fracture mechanisms involved excessive stress in an area under tension, leading to fatigue fracture. Male gender, high weight and young age were risk factors, as in the literature for fatigue fracture. Location and depth of laser etching induced fatigue fracture. The study demonstrated that laser etching creates an area of weakness in the implant neck and should therefore be eschewed in this part of the femoral stem.

LEVEL OF EVIDENCE

IV, retrospective study.

Compared fixation and survival of 280 lateralised vs 527 standard cementless stems after two years (1-7)

BACKGROUND

Restoring the native hip anatomy increases hip prosthesis survival, whereas increased femoral lateralisation creates high torque stresses that may alter prosthesis fixation. After finding lucent lines around cementless lateralised stems (Corail™, DePuy Synthes, St Priest, France) in several patients, we evaluated the effects of lateralisation in a large case-series. The objective of our study was to compare lateralised vs standard stems of identical design in terms of radiological osteo-integration and survival.

HYPOTHESIS

Lateralised stems, despite being used only when indicated by the anatomical parameters, carry a higher risk of impaired osteo-integration.

MATERIALS AND METHODS

A retrospective study was conducted in 807 primary total hip arthroplasties (THAs) performed between 2006 and 2010 in 798 patients with a mean age of 65 ± 14.2 years. Lateralised stems were used in 280 cases (Corail High Offset KHO, n = 169; and Corail coxa vara KLA, n = 111 cases) and standard stems in 527 cases (Corail KA). Mean follow-up was 2.3 years (range, 1-7 years). The clinical evaluation included determination of the Postel-Merle d'Aubigné (PMA) score. Bone fixation and stability of the implants were assessed by determining the Engh and Massin score and the ARA score on the radiographs at last follow-up. Femoral, acetabular and global offset values were determined before and after THA. Nobles's Canal Flare Index was computed. Survival was estimated using the Kaplan-Meier method with surgical revision for aseptic loosening as the end-point.

RESULTS

The PMA score improved from 12 (10-15) pre-operatively to 17.7 (14-18) (P < 0.05). After THA, in the lateralised stem group, femoral offset was restored in 217 (77%) hips and the mean change vs the pre-operative offset value was -2 mm; in the standard stem group, femoral offset was restored in 440 (83.5%) hips and the mean change was +1 mm. The Engh and Massin score values were similar in the standard stem and lateralised stem groups (24.4 ± 2.2 and 22.6 ± 2.4, respectively, NS). Revision for aseptic loosening was required in 5 patients with lateralised stems (3 KHO and 2 KLA) versus none of the patients with standard stems. There were no cases of excessive femoral offset and the mean change in offset was -2.3mm (-5.3 to -1.1). Noble's index was increased (4.27 ± 0.5 for the loosened lateralised stems, 3.65 ± 0.8 for the well-fixed lateralised stems and 3.82 ± 0.6 for the standard stems), with no significant difference across groups. Overall survival after 3.5 years of follow-up was 94.6% (95% confidence interval, 88.4-100%) with lateralised stems and 100% with standard stems (P < 0.05).

DISCUSSION

The risk of aseptic loosening was significantly higher with the lateralised stem (5/280, 1.8%) than with the standard stem (n = 0). Our findings indicate a need for careful preparation to obtain primary fixation of lateralised stems.

LEVEL OF EVIDENCE

III, retrospective case-control study.

Morbidity and mortality after surgery for cancer of the oesophagus and gastro-oesophageal junction: A randomized clinical trial of neoadjuvant chemotherapy vs. neoadjuvant chemoradiation

OBJECTIVE

To compare the incidence and severity of postoperative complications after oesophagectomy for carcinoma of the oesophagus and gastro-oesophageal junction (GOJ) after randomized accrual to neoadjuvant chemotherapy (nCT) or neoadjuvant chemoradiotherapy (nCRT).

BACKGROUND

Neoadjuvant therapy improves long-term survival after oesophagectomy. To date, evidence is insufficient to determine whether combined nCT, or nCRT alone, is the most beneficial.

METHODS

Patients with carcinoma of the oesophagus or GOJ, resectable with a curative intention, were enrolled in this multicenter trial conducted at seven centres in Sweden and Norway. Study participants were randomized to nCT or nCRT followed by surgery with two-field lymphadenectomy. Three cycles of cisplatin/5-fluorouracil was administered in all patients, while 40 Gy of concomitant radiotherapy was administered in the nCRT group.

RESULTS

Of the randomized 181 patients, 91 were assigned to nCT and 90 to nCRT. One-hundred-and-fifty-five patients, 78 nCT and 77 nCRT, underwent resection. There was no statistically significant difference between the groups in the incidence of surgical or nonsurgical complications (P-value = 0.69 and 0.13, respectively). There was no 30-day mortality, while the 90-day mortality was 3% (2/78) in the nCT group and 6% (5/77) in the nCRT group (P = 0.24). The median Clavien-Dindo complication severity grade was significantly higher in the nCRT group (P = 0.001).

CONCLUSION

There was no significant difference in the incidence of complications between patients randomized to nCT and nCRT. However, complications were significantly more severe after nCRT.

REGISTRATION TRIAL DATABASE

The trial was registered in the Clinical Trials Database (registration number NCT01362127).

Bile duct injuries following laparoscopic cholecystectomy

INTRODUCTION

Bile duct injuries occur rarely but are among the most dreadful complications following cholecystectomies.

METHODS

Prospective registration of bile duct injuries occurring in the period 1992-2013 at a tertiary referral hospital.

RESULTS

In total, 67 patients (47 women and 20 men) with a median age of 55 (range 14-86) years had a leak or a lesion of the bile ducts during the study period. Total incidence of postoperative bile leaks or bile duct injuries was 0.9% and for bile duct injuries separately, 0.4%. Median delay from injury to repair was 5 days (range 0-68 days). In 12 patients (18%), the injury was discovered intraoperatively. Bile leak was the major symptom in 59%, and 52% had a leak from the cystic duct or from assumed aberrant ducts in the liver bed of the gall bladder. Following the Clavien-Dindo classification, 39% and 45% were classified as IIIa and IIIb, respectively, 10% as IV, and 6% as V. In all, 31 patients had injuries to the common bile duct or hepatic ducts, and in these patients, 71% were treated with a hepaticojejunostomy. Of patients treated with a hepaticojejunostomy, 56% had an uncomplicated event, whereas 14% later on developed a stricture. Out of 36 patients with injuries to the cystic duct/aberrant ducts, 30 could be treated with stents or sphincterotomies and percutaneous drainage.

CONCLUSION

Half of injuries following cholecystectomies are related to the cystic duct, and most of these can be treated with endoscopic or percutaneous procedures. A considerable number of patients following hepaticojejunostomy will later on develop a stricture.