Aims

As has been shown in larger animal models, knee immobilization can lead to arthrofibrotic phenotypes. Our study included 168 C57BL/6J female mice, with 24 serving as controls, and 144 undergoing a knee procedure to induce a contracture without osteoarthritis (OA).

Background

An improved understanding of intervertebral disc (IVD) structure and function is required for treatment development. Loading induces micro-fractures at the interface between the nucleus pulposus (NP) and the annulus fibrosus (AF), which is hypothesized to induce a cascade of cellular changes leading to degeneration. However, there is limited understanding of the structural relationship between the NP and AF at this interface and particularly response to load. Here, X-ray scattering is utilised to provide hierarchical morphometric information of collagen structure across the IVD, especially the interface region under load.

Aims

Outcomes of current operative treatments for arthrofibrosis after total knee arthroplasty (TKA) are not consistently positive or predictable. Pharmacological in vivo studies have focused mostly on prevention of arthrofibrosis. This study used a rabbit model to evaluate intra-articular (IA) effects of celecoxib in treating contracted knees alone, or in combination with capsular release.

Aims

Arthrofibrosis is a relatively common complication after joint injuries and surgery, particularly in the knee. The present study used a previously described and validated rabbit model to assess the biomechanical, histopathological, and molecular effects of the mast cell stabilizer ketotifen on surgically induced knee joint contractures in female rabbits.

Recent studies about hip stability after total hip arthroplasties (THA) concerned differences regarding bearings: ceramic on ceramic (CoC) presenting less dislocations on the long term compared to metal or ceramic on polyethylene. The hypothesis is a difference in the healing process of periarticular tissues, with a stronger fibrous tissue for the first one, and more foreign body reaction, joint effusion with the others.

NMR Imaging of the pelvis showing both hips using novel MR MAVRIC program for metal artefacts suppression, were performed in 10 patients, 15 THA and 2 non-pathological contralateral hips. Eight hips had CoC bearings, 3 of which were impacted cementless bulky ceramic implant, and 5 had a metal back. 7 hips had CoP bearings, 4 of which were cemented.

Native capsules showed a mean thickness of 6.6mm. For CoC bearings, capsule thickness ranged from 7mm to 9.6 mm with a mean thickness of 8mm. For CoP bearings, capsule thickness ranged from 3mm to 8.4mm, with a mean thickness of 6.1mm. Neocapsule appeared clearly in all COC bearings observed, while for CoP, sometimes it was less dense with fatty aspect, 3 hips out of 7 having a very thin capsule under 4mm.

It is possible to observe and quantify new capsule after THR and measure differences although not significant regarding bearings on limited number of samples. More patients might be included, but the tendencies observed here might explain better long term stability in vivo observed with Coc.

Objectives

Sustained intra-articular delivery of pharmacological agents is an attractive modality but requires use of a safe carrier that would not induce cartilage damage or fibrosis. Collagen scaffolds are widely available and could be used intra-articularly, but no investigation has looked at the safety of collagen scaffolds within synovial joints. The aim of this study was to determine the safety of collagen scaffold implantation in a validated in vivo animal model of knee arthrofibrosis.

Aims

Animal models have been developed that allow simulation of post-traumatic joint contracture. One such model involves contracture-forming surgery followed by surgical capsular release. This model allows testing of antifibrotic agents, such as rosiglitazone.

Summary

Based upon genetic analysis, decorin is an exciting pharmacologic agent of potential anti-fibrogenic effect on arthrofibrosis in our animal model.

Objectives

The goal of this study was to determine whether intra-articular administration of the potentially anti-fibrotic agent decorin influences the expression of genes involved in the fibrotic cascade, and ultimately leads to less contracture, in an animal model.

Background

Morton's neuroma is the enlargement of an interdigital nerve most commonly located between the third and fourth metatarsals. It is susceptible to entrapment and therefore is a common cause of disabling foot pain. Greek foot is a normal variant where the first metatarsal is shorter than the second metatarsal. To our knowledge there is currently no reported association between Greek foot and Morton's neuroma in the literature.

Purpose: Resection elbow arthroplasty is a salvage procedure typically considered as a last resort when other reconstructive options have failed. It was the intent of this study to evaluate the long-term outcome of patients following resection elbow arthroplasty.

Method: Fifty-four elbow resections performed between 1975 and 2005 were retrospectively reviewed. Pre and post-operative elbow function was evaluated with the Mayo Elbow Performance Score (MEPS) and additional follow-up data was compiled using the Disability of Shoulder and Hand (DASH) score. All patients in this study had a resection following a failed total elbow arthroplasty (TEA). Nineteen patients had died at time of follow-up, and 5 patients were lost to follow-up, leaving 30 of the surviving 34 patients (88%) available for long-term evaluation.

Results: The main indication for resection in this study was infection (50 of 54 elbows). The average MEPS prior to resection was 36. The long-term results in 30 patients at an average of 11 yrs (range 2.7–28 yrs) demonstrated an average MEPS score of 60, and a DASH score of 71. Complications were common including persistent infection requiring re-operation (44%), intra-operative fracture (32%), transient (11%) or permanent (5.5%) nerve damage, and one case of vascular injury requiring amputation. Achieving a stable resected elbow correlated strongly with a good long-term MEPS score (r=0.75).

Conclusion: This study emphasizes the difficulty in treating patients with a failed total elbow arthroplasty. Resection arthroplasty is a salvage procedure indicated primarily for persistently infected TEA and results in satisfactory outcomes in this population.

Introduction: Nowadays, the use of antibiotic-impregnated cement in revision total knee arthroplasty procedures is widespread, and a substantial body of evidence demonstrates its efficacy in deep infection prevention

Nevertheless, it is not clear that it is necessary or desirable as a routine means in primary total knee arthroplasty.

Some European studies demonstrate that the use of antibiotic-impregnated cement, shows to be effective in the prevention of early to intermediate deep infection following primary total knee artrhoplasty

Material and Methods: A retrospective review of 642 primary total knee arthroplasties (Legacy-Zimmer) was made between 2003–2006

Two groups were established:

A group of 296 patients with a primary total knee arthroplasty cemented without impregnated antibiotic.

The mean follow up was 12 months.

We analyze the differences in the infection rate between the two groups, within the first year of follow-up

Results: No significant differences were found between groups in terms of demographic variables, surgical procedure duration, tourniquet time, postoperative blood transfusion index or medical complications.

10 postoperative deep infections were found in the antibiotic non-impregnated cement group (3.3% of infection)

A comparative analysis was performed which showed to be statistically significant.

Conclusions: Gentamycin-impregnated cement shows statistically significant effectiveness in the prevention of early to intermediate deep infection following primary total knee artrhoplasty

For the treatment of the fractures of the proximal extremity of the femur two predominant systems exist: the intramedular nail and the sliding screw plate.

The variables at the moment, to be considered, are the weight, age and type of fracture. The principal aims are: To develop models of finite elements of both types of implants and of two types of fracture (stable and unstable), and to integrate the models of finite elements of the implants in the model of fractured femur, to obtain the mechanical behavior of both types of implants and them to fit to the model of finite elements.

The analyzed models have been the gamma-3 nail (Stryker, USA) and the PerCutaneus Compression Plate (PCCP), (Gotfried, Israel). The real geometry has been created in the program SolidWorks 11.0 to be treated later in the program of calculation by means of finite elements Ansys.

The assembly with nail is more rigid (11.51 mm) that with plate (11.95 mm) on having had a few minor displacements. The tensions that appear in the nail (446 MPa) are major that those of the plate (132.93 MPa), in the unstable fractures.

In the unstable fractures, the intramedular nail is more rigid than the system of plate. The tensions to which the nail meets submitted are superior to those of break for what the nail would not be capable of supporting the first cycles of load. It is for it, that the system to using in these cases would be the sliding screw plate.

Introduction: The open approach for releasing the A1 pulley shows high dissatisfaction rates. Percutaneous blind release is as an alternative achieving similar effectiveness and better results but the lack of visualization puts at risk the adjacent anatomy and its indicated only for the 3rd and 4th fingers. Recently, an effective percutaneous method for releasing A1 in every finger has been described assisted by the visualization with ultrasounds (US). Despite the reported safety, this US-technique poses a risk to the adjacent anatomy due the orientation of the blade. Our purposes were to develop a new percutaneous US-guided A1 release (USGAR) that lessens the risk to adjacent anatomic structures and to determine the precision, safety and efficacy of our USGAR.

Methods: To determine how to lessen the risk to adjacent structures, a descriptive study with a power-Doppler US (Logiq Book XP Pro 5–11 MHz, GE) was done in 100 fingers from 10 volunteers (3 females and 7 males; mean age 29,8 years, range 25–49 years). Measurements, on a transverse section of A1, included: lateral vascular angle (LVA), medial vascular angle (MVA), distance to lateral artery (DLA), distance to medial artery (DMA), lateral latitude (LL), medial latitude (ML), pulley thickness (PT) and synovial space width (SW).

A descriptive study was developed in 5 formaldehyde preserved cadavers, 50 fingers (3 men and 2 women, average age at time of death 60,6 years, range 52–81). US identification of topographic markings was followed by USGAR and open dissection. Measurements included real (RL) and US (UL) A1 length and distances from: markers to proximal (MP) and distal A1 edges (MD); markers to A2 (MA) and neurovascular (NV) bundles (MN); and from the surgical release to A2 (SA) and NV (SN). The length of any incomplete release (IR) and damage to adjacent structures were recorded. Mean values, Standard deviation and range were gathered. ANOVA was used to analyze differences (significant at p < 0.05).

Results: In our volunteers, we obtained the following values (degrees or mm): LVA, 20,9 +/− 14,03 (0/83,7); MVA, 23,3 +/−13,06 (0/61,5); DLA, 8,96 +/−3,08 (3,5/20,6); DMA, 7,59 +/−2,56 (3,7/16,8); LL, 2,38 +/−1,53 (−1/6,5); ML,: 2,56 +/−1,84 (0/10,8); PT, 0,79 +/−0,22 (0,2/1,5); SW, 0,33 +/−0,19 (0,1/0,9). Differences were not significant among fingers. In our group of cadavers our findings (mm) were: RL, 10,1 +/−1,36 (8/13); UL, 10,84 +/−1,38 (8/14); MP, −0,56 +/−1,3 (−5/2); MD, −0,19 +/−0,95 (−4/2); MA, 4,56 +/−1,64 (1/9); MN, 18,78 +/−4,11 (11/27); SA −1,08 +/−1,67 (−5/2); SN −13,17 +/−3,55 (−22/−6). There was a 1 mm IR in 2 fingers and minor puncture-like erosions in 6.

Conclussion: Our new method for USGAR minimizes the risk of accidental damage to adjacent anatomic structures. The method is precise, effective and safe in cadavers. This has set the bases for a clinical phase at our Institution.

Introduction: The study of appearance and development of the different ossification nuclei of the skeleton in the diverse segments of the locomotor apparatus is relevant for fields of medicine, such as Human Anatomy, Paediatry, Endocrinology, Forensic Medicine, Traumatology and Orthopaedic Surgery, among others.

A number of studies show significant differences regarding their results due to the heterogeneity of methods and scientific and geographic fields originating each series.

The present study is intended to show the age of appearance and complete fusion of the different ossification nuclei of the first radio of the foot in a present Mediterranean sample of children and its relation with several morphometric and clinical parameters.

Material and Methods: We report a retrospective study where 971 x-ray dorso-plantar images from 225 patients were analysed.

A descriptive and qualitative assessment allowed us to determine the existence or lack of each ossification nucleus of the first radio of the foot. Risser’s scale, adapted by us, was applied in the following way: 0, lack; I, rudimentary nucleus; II, well formed nucleus; III, partial fusion to diaphysis; IV, complete fusion.

Likewise, a statistical analysis was performed relating the ages of appearance and fusion of each nucleus with the forefoot morphology (digital and metatarsal formulae) and the main pathologies motivating the x-ray examination (traumatism, our control group; flatfoot; hallux valgus; clubfoot).

Results: Data about the age of appearance and fusion of each nucleus of the first radio of the foot were quantified.

As a general rule, the age of appearance of each nucleus was earlier in girls. A delay in the age of appearance of the proximal metatarsal epiphysis in clubfoot patients (3.33 years) was observed in comparison with the control group (1.96 years).

In general, there was no relation between sex and the fusion (partial and total) of each nucleus of the first radio of the foot. The exception was the age of appearance of the distal metatarsal epiphysis (when this incostant nucleus was present), earlier in boys (9.49 years) than girls (11.21 years).

A delay in the age of fusion of the proximal and distal metatarsal epiphyses and the proximal phalanx epiphysis was observed in hallux valgus patients.

In patients with egyptian foot, there seems to be a delay in the age of fusion of the distal metatarsal and distal phalanx epiphyses.

Conclusions: The different ages of appearance and partial and total fusion of each ossification secondary nucleus of the first radio of the foot are detailed in the present comunication. A delay in the age of fusion of the secondary nucleus of the first radio of the foot would contribute to determine significantly forefoot morphology (egyptian formula) and even its pathology (hallux valgus).

Purpose: The long-term experience of linked semicon-strained total elbow arthroplasty was investigated as a salvage procedure for patients with distal humerus non-union not amenable to internal fixation.

Method: Ninety-two consecutive total elbow arthroplasties performed for the treatment of a distal humeral nonunion were reviewed at an average follow-up of 6.5 years (range, 0.5 to 20.3 years). There were twenty-two men and sixty-nine women with an average age of sixtyfive years (range, twenty-two to eighty-four years) at the time of elbow replacement. Seventy-six elbows (83 per cent) had undergone prior surgery, with an average of two previous operations (range, one to ten). Five elbows had had at least one prior operation due to infection.

Results: Seventy-nine per cent of the patients had no pain or mild pain at latest follow-up compared with moderate or severe pain in 86 percent prior to surgery. Mean extension was improved from thirty-seven to twenty-two degrees and mean flexion from 106 to 135 degrees. Joint stability was restored in all patients, including nine with a grossly flail elbow. Complications included aseptic loosening in sixteen (four with periprosthetic fractures), component fracture in five, deep infection in five (three with previous infection), and bushing wear in one patient. At most recent follow-up, 85 per cent of the patients were satisfied with their outcome. Survivorship for not requiring removal or revision for any cause was 95.7 per cent at two years, 82.1 per cent at five years, 65.3 per cent at ten and fifteen years. Factors that increased the risk of implant failure were patient age less than sixty-five, two or more prior surgeries, and history of previous infection.

Conclusion: Linked semiconstrained total elbow arthroplasty provides a reliable salvage procedure to provide pain relief and restoration of motion and function in patients with distal humerus nonunion not amenable to internal fixation. Risk factors for failure include younger patients, multiple previous surgeries, and history of infection.

Purpose: We conducted a retrospective review to evaluate outcomes, complications and implant survival after shoulder reconstruction for bone neoplasm using anatomic shoulder prostheses.

Method: Thirty-four anatomic shoulder prostheses were reviewed at an average follow-up of 51 (range, 6 to 143) months. The mean age at the time of surgery was 47 (range, 15 to 74) years. Twenty-five patients (74%) had reconstruction with an allograft-prosthetic composite (APC). The average amount of humerus resected in patients with an APC was 13 cm (range, 5 to 36 cm).

Results: At most recent follow-up, 82% of patients had no pain (11), slight pain (12) or moderate pain with strenuous activities (5). Twenty-eight patients (82%) were subjectively satisfied despite only 29% being satisfactory according to Neer rating. Sixteen complications occurred in 13 patients, including instability (5), host/graft non-union (3), aseptic loosening (3), arthrofibrosis (1), tumor recurrence (2) and superficial infection (1). Host/graft nonunion occurred in 3/9 patients with an APC using press-fit or plate fixation for distal humeral fixation and 0/16 shoulders with cemented distal humeral fixation (p=0.02). Three implants required revision for aseptic loosening (1), host/graft nonunion (1) and instability (1). Kaplan-Meier survivorship at 10 years was 88% for implant revision and 80% for mechanical failure.

Conclusion: Reconstruction of the proximal humerus using an anatomic prosthesis after resection of bone neoplasms is associated with a low rate of mechanical failure but a moderate rate of shoulder instability. Cement fixation into the native distal humerus should be considered when reconstruction using an APC is required.

Purpose: Loosening of the humeral component is rarely a cause for revision shoulder surgery. Most long-term series are not large enough to stratify the many risk factors that might influence the survivorship of humeral component designs. The purpose of this study was to determine long-term survivorship of the Neer and Cofield humeral components and to define the risk factors associated with humeral component removal or revision.

Method: 1584 primary Neer and Cofield shoulder arthroplasties (1423 patients) were performed at our institution from 1984 to 2004. There were 619 men (694 shoulders) and 804 women (890 shoulders), with a mean age at arthroplasty of 65.6 years (range, 16–94 years). Kaplan-Meier survivorship analysis was used to determine the effect of etiology of the disease, gender, age, surgery type (hemi versus total), fixation type (cemented versus noncemented), and the humeral component type (Neer II, Cofield I or II) on the estimated survival free of humeral component revision or removal.

Results: There were 108 revisions and 17 removals of the humeral component. The overall rate of removal or revision of the humeral component was 7.9% with an average followup of 8.1 years. The rates of survivorship free of revision or removal of the humeral component for any reason was 94.8% at 5 years, 92% at 10 years, 86.7% at 15 years and 82.8% at 20 years. Seventy-one of 632 shoulders (11.2%) in patients younger than 65 years required humeral component revision or removal, whereas only 54 of 952 shoulders (5.7%) in patients 65 years and older required humeral component revision or removal (Odds ratio=2.1; 95% confidence interval, 1.5–3, p=0.001). Patients with posttraumatic arthritis had a higher risk of needing revision or removal of the humeral component (Odds ratio=2.1, 95% confidence interval 1.3–3.3) compared to osteoarthritis. Eighty-four of 526 shoulders (16.0%) with metal-back glenoid components required humeral component revision or removal, whereas only 41 of 1058 shoulders (3.9%) with non metal-backed glenoid components required humeral component revision or removal (Odds ratio=4.7; 95% confidence interval, 3.2–7, p=0.001).

Conclusion: Younger age, replacement due to post-traumatic arthritis and presence of a metal-backed glenoid increased the likelihood of humeral component failure. Similar short-term survival can be achieved with Cofield II and Neer II humeral components.

The purpose of this study is to report our experience with revision of total elbow arthroplasty by exchange cementation. Between 1982 and 2004 at our institution, forty six elbows were treated with exchange cementation of a total elbow arthroplasty into the existing cement mantle or debrided bone interface, without the use of an osteotomy, bone graft or prosthetic augmentation. Indications for the procedure were aseptic loosening (17), second stage after septic loosening (14), instability (7), prosthetic fracture (4), periprosthetic fracture (2), failed hemiarthroplasty (1) and ulnar component wear (1). Both components were exchanged in 18 elbows, the humerus alone in 25 and the ulna in 3. Mean follow up was 90.5 months (10 to 266 months);18 patients had died with the prosthesis in situ. Complications were noted in 22 elbows; periprosthetic fracture of ulna (6) and humerus (2), humeral component fracture (1), aseptic loosening (4), non-union (1), heterotrophic ossification (2), soft tissue contracture (2) and soft tissue failure (2), delayed wound healing (1) and bushing failure (1). Reoperation was required in 10 elbows for revision of both components (2), ulna (3), humerus (1), bushing revision (2), soft tissue debridement (1) and soft tissue repair (1). There were no septic recurrences in previously infected elbows; however the reoperation rate in this group was 29% versus 19% after re-cementation for other causes. Revision of total elbow arthroplasty by exchange cementation is a reasonable treatment for those elbows with adequate bone stock for secure prosthetic fixation; however careful consideration should be given to augmentation of the ulna due to the high rate of periprosthetic fracture in this series. Re-cementation following débridement for infection is effective despite having a higher rate of revision operation compared to re-cementation in the aseptic elbow.

Introdution. Gamma sterilisation in air produces free radicals in the polyethylene (PE) with the result of degrading its mechanical properties, increasing wear and debris, and producing osteolysis and loosening. PE sterilized in the absence of air and high cross-linked polyethylene (HXLPE) have been used to avoid osteolysis and loosening. This prospective randomized study has assessed results in a series using two different poly-ethylenes associated with the same prosthetic design.

Methods: We assessed 45 Allofit cups with Sulene-PE liner (sterilized with nitrogen) and 45 Allofit cups with Durasul-PE liner (HXLPE), both associated with an Alloclassic stem (28-mm femoral head) (Zimmer). The minimum follow-up is 5 years and the mean follow-up 66.3 months. The linear femoral head penetration was estimated at 6 weeks, at 6 and 12 months and annually thereafter, using a software package employing the Dorr method, given the nonspherical cup shape.

Results All assessed hips had good clinical and radiographic results. There was no loosening of any prosthetic component. There were no radiolucent lines or osteolysis. Femoral head penetration in the early postoperative radiographs was 47.4% less in the Durasul group (0.09+0.03 mm) than the Selene-PE group (0.19+0.06 mm)(p< 0.0001). The mean yearly linear femoral head penetration was 20% lower in the Durasul group (0.008+0.008) than the Sulene-PE group (0.04+0.02)(p< 0.0001). Differences increase after the third year. Mean linear femoral head penetration at 5 years was 39.1% less in the Durasul group (p< 0.0001).

Conclusions: Although the digitized method used is not totally accurate and is used only for a general estimate, there is a significant reduction in yearly linear femoral head penetration with Durasul-PE. Longer-term results are needed to confirm that this polyethylene generates less osteolysis.