Pre-operative definitive diagnosis of infection in painful total hip arthroplasty (THA) is not always easy to be established, making the intra-operative decision-making process crucial in management of revision hip surgery. Calprotectin is a promising point-of-care novel biomarker that has displayed high accuracy in detecting PJIs.

From November 2020 to December 2022, 105 patients with painful primary THA were treated with revision THA in 3 orthopaedic departments. Pre-operatively, 23 were considered infected and treated with two-stage revision THA. The remaining 82 were likely infected according to the 2019 EBJIS criteria. The suspicion of low-grade infection was based on clinical (rest and/or night pain), laboratory (CRP, ESR, WBC – normal or slightly elevated) and radiological evaluation (loosening). Hip aspiration under CT imaging was performed in these cases and 34 of them yielded positive culture and were treated with two-stage revision. Aspiration was ineffective in the remaining 48 cases (33 negative, 15 unsuccessful attempts). Intra-operatively, calprotectin was measured with lateral flow immunoassay test in these patients. Cases with calprotectin levels ≥ 50 mg/L were treated with 2-stage revision THA; otherwise, they were considered not-infected and one-stage revision was performed. Synovial fluid and tissue samples were collected for analysis. Implants were sent for sonication fluid cultures.

Calprotectin was positive (≥ 50 mg/L) in 27 cases and negative in 21 cases. There was 1 false negative case with positive tissue cultures. Out of the 27 positive cases, 25 had positive tissue cultures and sonication. However, 2 cases with high calprotectin levels (>200 mg/L) were not infected. The false positive result was attributed to severe metallosis. Calprotectin sensitivity was 96.2%, specificity 90.9%, PPV 92.6%, NPV 95.2%, AUC 0.935.

The results of this ongoing study indicate that calprotectin seems to be a valuable tool in facilitating the intra-operative decision-making process in cases that low-grade infection is suspected and diagnosis cannot be established pre-operatively.

To determine the gross structural alterations of the nailed bone (femur or tibia) after the removal of an intramedullary nail (IMN).

Eighteen patients (14 femoral and 4 tibia nail) underwent an IMN removal from their femur or tibia. Every patient had a spiral computed tomography scan and a plain X-ray study, immediately after the nail removal and also at their latest follow-up (24–30 months). The 4 patients with a tibia nail were additionally examined using a peripheral quantitative computed tomography study at their latest follow-up. All patients were asymptomatic.

An intramedullary shell of compact bone was demonstrated around the nail track. This new bone was apparent on plain radiographs in all of the patients. Peripheral quantitative computed tomography study revealed that the density of the bony ring was similar to that of subcortical bone. The histologic examination of the intra-medullary shell of one of our patients suggested that the bony ring was made of cortical bone.

Intramedullary nailing may enhance new cortical bone formation within the bone marrow cavity. This “cortical bone” still exists more than 2 years after implant removal. Nail insertion also causes thickening of the normal cortex at the sites of nail–cortex contact where loads are transferred from the nail to the cortex. This new finding could probably lead the research of intramedullary nailing biomechanics toward new directions as to understand the body’s reaction to IMNs.

This study concerns an epidemiological analysis of foot and ankle injuries during the Athens Olympic Games 2004.

An epidemiological survey was used to analyse injuries in all sport tournaments over the period of the Games. During the Athens Olympic Games 2004 in the period from August 1st to September 1st, 624 patients presented to the Foot and Ankle Department for treatment. The mean age of athletes was 24 years (range 21 to 32). Among the patients there were more males, 358 (58%) than females, 266 (42%).

In 525 (84.1%) patients there was only a soft tissue injury and in 99 (15.9%) patients there was bone involvement. Regarding specific diagnoses, tendinitis was the most common reason for a visit, followed by ankle sprains, nail infections/injuries, lesser toes sprains, and stress fractures. Sixty-nine (11%) required emergency transfer to the hospital.

Our experience from the Athens Olympic Games will inform the development of public health surveillance systems for future Olympic Games, as well as other similar mass events.

Objective: we present the long-term behavior of polyethylene’s insert in acetabular implants ARC2F.

Materials and Methods: from 1989 to 1995, 668 THA’s were implanted. Mean patients age was 54 years (28–75). The preoperative diagnosis included: primary OA 501 cases, post-traumatic arthritis 24, hip dysplasia 112, AVN 31. In all cases Omnifit femoral stem with proximal HA coating and ARC2F acetabular component were used. 165 patients (182 arthroplasties) were lost to follow-up. The average time of observation was 15 years (13–18.5).

Results: all THA’s performed well without signs of wear at 10 years. No implant was revised during the first decade because of mechanical loosening. Since then, during the 13th – 14th year, a significant number of patients appeared with symptoms of polyethylene’s massive destruction and significant osteolysis at the femoral and acetabular side of the arthroplasty. We recalled all patients that could be found. Totally, 178 from 486 THA’s had similar radiographic signs of wear. Only 33 of all these had initial wrong orientation of the cup.

Conclusion: despite the excellent early and middle-term results, ARC2F shows rapid and massive wear of the insert after 12 years, probably because of degeneration and loss of polyethylene’s structural integrity due to the method of sterilization. We suggest to recall and inspect all the patients which have this kind of implant more than 12 years.

Objective: The presentation of mid-term results of porous tantalum TMT cup in congenital high hip dislocation.

Materials and Methods: Between November 1997 and December 2000, we performed 27 total hip replacements in 22 women patiens suffering from high congenital hip dislocation according Xartofilakidis classification. The acetabular component was implanted at the true acetabular bed with restoration of the centre of hip rotation. Clinical and radiological observation took place in regular intervals for an average time of 10.2 years (8.5–12 years).

Results: The average Harris Hip Score improved from 48.3 preoperatively (range 15–65) to 89.5 at the latest follow-up (56–100). Oxford hip score declined from 49.5 preoperatively to 21.2 at the first year and to 15.2 at five years examination. The absolute acetabular component’s migration was evaluated by EBRA method in the first 2 years and was at average 0.85 mm at the first year and 1.05 mm at the second year. An incident of gross initial migration was observed. No acetabular revision was performed and there was no case of mechanical loosening.

Conclusion: The acetabular TMT component is highly adhesive and porous with a modulus of elasticity close to subchondral bone. It promotes initial stability, induces bone penetration and integration and offers a more “physiologig” load transfer. It also offers adequate polyethylene thickness, even in the smallest sizes, due to its manufacturing. The recent results from its use in high hip dislocation are excellent and justify the further study of longevity and probably the superiority of this material.

Purpose: To present a series of 49 patients which underwent single or two staged complete spondylectomy, vertebral body reconstruction and segmental spinal stabilization due to spinal tumors.

Materials and Methods: From 1992 to 2002, 49 patients with primary or metastatic spinal tumors were treated. There were 36 females and 13 males with mean age at operation of 53.5 years (19 – 80). The preoperative classification was Frankel E in 17 cases, B – D in 31 cases and A in one case. Five patients had nerve root dysfunction and one, classified as Frankel E, had sphincter inadequacy. The parts of the spine involved were lower cervical in 7 cases, thoracic in 10, thoracolumbar in 15 and lumbar in 17 cases. The operations were two staged in 36 cases and single staged in 13 cases. In the cervical spine, titanium cylinders filled with methylmethacrylate were used. For the rest of the spine, the most commonly used instruments were the Kaneda device, followed by the Miami–MOSS system. Bone graft was used in five benign tumors. Mean follow – up was 62.3 months.

Results: One patient died during the anterior procedure and in another it had to be interrupted, whereupon he died one week later. Two patients died due to their underlying pathology in the 6th post–operative month. Complications included wound healing problems in 9 patients and local recurrence in one patient. There were no neurological deteriorations or instrument failures. The majority of patients experienced improvement in their neurological status, reduction of pain or both. Most patients were functionally improved and spinal alignment was maintained in all.

Conclusion: Spinal tumor resection and spinal reconstruction provide stability, early weight bearing, symptom remission and neurological improvement.

Purpose: To describe the diagnostic planning and treatment modalities of six patients with this rarest of sacral fractures. Due to the low incidence of these injuries, there is no literature evidence concerning their management.

Materials and Methods: Six patients with a transverse fracture of the sacrum with anterior displacement. All patients were admitted with bowel and bladder dysfunction, perineal anesthesia, sensory and motor deficits at the lower extremities. Prompt diagnosis of the sacral fracture was obtained in five of the six patients.

Results: Operative treatment including extensive lumbosacral laminectomies, spine instrumentation and fusion was performed in all cases. Neurological recovery was almost complete in one patient, partial in 4 patients and absent in one patient.

Conclusions: A more favorable clinical outcome can be achieved when operative treatment is implemented using lumbosacral decompression by laminectomy, dural repair and posterolateral instrumented fusion with bone grafting. Although reduction of the fracture was not ideal in many of these patients, long term clinical and radiographic follow – up as well as neurological improvement were rewarding.

Aim of the study: To define the dimensions of the radial head, as well as the radiocapitellar and proximal radio-ulnar joints. The most congruent portions of the radial head articulations were determined.

Materials & Methods: Computed tomography scans of twenty-two cadaveric adult elbows were obtained in three forearm positions – supination, neutral, pronation. The radial head dimensions, the radiocapitellar joints, and the proximal radioulnar joints were also measured. Multivariate analysis of variance was used to determine which portions of each articulation were the most congruent.

Results: At the level of the radial trough, the maximum diameter was 22.3 mm, the minimum diameter was 20.9 mm, and the diameter difference was 1.4 mm. This difference represented only 6.3% of the overall maximum diameter. The depth of curvature of the radial head trough was 2.3 mm, the radial head length was 9.8 mm, and the radial neck length was 10.7 mm. At the isthmus of medullary canal, the maximum diameter was 9.7 mm, the minimum diameter was 8.2 mm, and the diameter difference was 1.5 mm. This difference represented 15.6% of the maximum diameter. The average radiocapitellar distance at the radial lip was 4.0 mm, the trough 2.4 mm, and the ulnar lip 2.2 mm. Thus, the radial head tended to become uncovered at the radial lip (p < 0.0001). The radiocapitellar joint was tighter in pronation than in supination (p = 0.0008). The proximal radioulnar joint was most congruent at the MPRUJ (middle proximal radioulnar joint), at the midportion and posterior aspects, rather than the anterior aspect (p < 0.0001). The PRUJ coverage was between 69.0 and 79.2 degrees.

Conclusions: Prosthesis trial sizing should be judged by the articulations providing the most congruency –

1) the ulnar lip or trough of the radiocapitellar joint in pronation and

Aim: The posterior interosseous nerve (PIN) is often at risk during surgical approaches to the proximal radius. The forearm is pronated during the approach to retract the PIN further away from the dissection. We hypothesized that a fracture of the radius would decrease the protection provided by the pronation maneuver.

Material and Methods: The position of the PIN in cadaveric elbows was measured using CT scans made after the PIN sheath was injected with radiopaque dye. Senventeen elbows were injected and CT scans were made in both full supination and pronation. The same elbows then had a radial osteotomy performed at the proximal-middle third junction and were re-scanned in supination and pronation. Finally the same elbows had the fascia around the osteotomy sutured and were scanned a third time. Measurements on the axial CT scans at the level of the radial head were taken of the angle formed by the olecranon, head, and PIN, as well as of the distance between the PIN and the lateral most aspect of the radial head.

Results: In the control group with intact radii, pronation increased the distance between the lateral radial head and the PIN by 6.44 mm. With radial osteotomy, the mean increase was 3.88 mm. The excursion of the nerve along the long axis of the radius decreased from 29.6 degrees to 23.3 degrees.

Conclusions: Radial osteotomy decreased the excursion of the PIN provided by pronation for the forearm by 40%. The Kocher approach requires additional care in light of a radial shaft fracture, but pronation is still beneficial.