Palmar multidirectional fixed-angle plate fixation in distal radius fractures: do intraarticular fractures have a worse outcome than extraarticular fractures?

Introduction

The results and complications using a palmar plate system with the possibility of multidirectional fixed-angle screw fixation (Aptus^® Radius 2.5 mm by Medartis^®) for the treatment of unstable distal radius fractures were evaluated in a single cohort study including 62 patients.

Patients

Patients with extra- and intraarticular fractures were evaluated separately. The mean follow-up was 14.7 months. Active wrist motion averaged 60.1° extension, 52.0° flexion, 86.3° pronation, and 84.6° supination. Grip strength averaged 89% of the contralateral wrist.

Results

There was no loss of the initial reduction with bony union in all cases. The mean DASH-score was 12.6 points. Postoperative complications included two extensor pollicis longus tendon ruptures, two median nerve compression syndromes, one complex regional pain syndrome, and one postoperative haematoma. In our series the results of the intraarticular fracture group were similar to the extraarticular fracture group. The complication rate, however, was substantially higher in the intraarticular fracture group.

Conclusion

We conclude that palmar plating with multidirectional fixed-angle screw insertion is an effective and useful treatment option, especially for complex intraarticular distal radius fractures.     

An animal model in sheep for biocompatibility testing of biomaterials in cancellous bones

Background:

A commercially available nanocrystalline hydroxyapatite paste Ostim^® has been reported in few recent studies to surpass other synthetic bone substitutes with respect to the observed clinical results. However, the integration of this implantable material has been histologically evaluated only in animal experimental models up to now. This study aimed to evaluate the tissue incorporation of Ostim^® in human cancellous bone after reconstructive bone surgery for trauma.

Methods:

Biopsy specimens from 6 adult patients with a total of 7 tibial, calcaneal or distal radial fractures were obtained at the time of osteosynthesis removal. The median interval from initial operation to tissue sampling was 13 (range 3–15) months. Samples were stained with Masson-Goldner, von Kossa, and toluidine blue. Osteoid volume, trabecular width and bone volume, and cortical porosity were analyzed. Samples were immunolabeled with antibodies against CD68, CD56 and human prolyl 4-hydroxylase to detect macrophages, osteoblasts, and fibroblasts, respectively. TRAP stainings were used to identify osteoclasts.

Results:

Histomorphometric data indicated good regeneration with normal bone turnover: mean osteoid volume was 1.93% of the trabecular bone mass, trabecular bone volume – 28.4%, trabecular width – 225.12 μm, and porosity index – 2.6%. Cortical and spongious bone tissue were well structured. Neither inflammatory reaction, nor osteofibrosis or osteonecrosis were observed. The implanted material was widely absorbed.

Conclusion:

The studied nanocrystalline hydroxyapatite paste showed good tissue incorporation. It is highly biocompatible and appears to be a suitable bone substitute for juxtaarticular comminuted fractures in combination with a stable screw-plate osteosynthesis.     

Mid-term results of a new cementless hydroxyapatite coated anatomic unicompartmental knee arthroplasty

Introduction

We report the mid term results of a cement less HA coated unicompartmental knee prosthesis.

Material and methods

One hundred and fifty-nine Unicompartmental knee arthroplasties were done between 1995 and 2000 with ALPINA^® UNI, a cementless HA coated anatomic prosthesis. One hundred and twenty knees were available for the mid-term follow-up at a mean of 6.5 years.

Results

The mean IKS improved from 87.1 ± 22.1 points preoperatively to 168.2 ± 26.1 at the latest follow-up (P < 0.001). Ninety-four percent of the knees were rated good and excellent. The mean knee flexion has significantly improved from 120° preoperatively to 126° at the latest follow-up (P < 0.001). Ten knees were revised: three for degeneration of osteoarthritis in the opposite compartment of the knee, four for polyethylene insert fracture, one for severe polyethylene wear and two for tibial component loosening. When revision for any reason was defined as the end point, the 5-year Kaplan–Meier survival rate was 95.7% (95% confidence interval, 90.1–98.2%) and when revision due to implant mechanical failure (excluding degeneration of osteoarthritis in the opposite compartment of the knee) was defined as the end point, the 5-year survival rate was 96.6% (95% confidence interval, 91.2–98.7%).

Conclusion

This study confirms the reliability of HA coated unicompartimental knee replacement. With careful indications it seems to be a good alternative to osteotomy of total arthroplasty.     

Elastic stabilisation of proximal humeral fractures with a new percutaneous angular stable fixation device (ButtonFix®): a preliminary report

Introduction

The ButtonFix^® system represents a new angular stable percutaneous fixation device for stabilisation of fractures of the proximal humerus. The purpose of this study was to present a preliminary report of the radiological and clinical outcome after minimally invasive stabilisation of selected proximal humerus fractures with the ButtonFix^®.

Patients and methods

Seventeen patients with fractures of the proximal humerus were treated in our department with the ButtonFix^® system. The mean final follow-up was performed 19 months postoperatively. Follow-up included assessment of postoperative reposition, range of motion, the DASH score, the Constant–Murley score, and the Short Form 36 (SF36).

Results

Twelve patients showed anatomical head-to-shaft angles, four revealed minor valgus replacement, and one minor varus replacement. In one patient unplanned revision surgery was necessary due to early secondary fracture dislocation requiring ORIF with an angular stable form plate. Implant removal was performed after 6 weeks in all patients. At the final follow-up, mean range of motion was: flexion 135°, extension 45°, abduction 142°, internal rotation 51°, and external rotation 62°. The mean Constant–Murley score was 70. The mean DASH score was 26 points and the average SF36 score was 76 points. One patient showed radiological signs of avascular necrosis.

Conclusion

The ButtonFix^® system represents a valuable tool in the treatment of proximal humeral fractures with results indicating fewer complications compared to prior percutaneous fixation devices. Moreover, the ButtonFix^® seems to be able to maintain reduction even in elderly patients with potentially reduced bone mass.     

Minimally invasive and open surgical treatment of proximal tibia fractures using a polyaxial locking plate system: a prospective multi-centre study

Purpose

The purpose of this study was to determine whether a polyaxial locking plate of the latest generation (NCB PT®, Zimmer Inc.) which can be applied both open and minimally invasively, can be used as a routine method of treatment for proximal tibia fractures.

Methods

Eighty-six patients (35 women, 51 men; mean age 51 years) were enrolled in this prospective multicentre trial. Ninety-six percent of the fractures were intra-articular (AO type B and C); 36 % were treated open and 64 % minimally invasively. Follow-up was obtained three, six and 12 months after surgery.

Results

No implant failure occurred. At 12 months, the functional result using a knee-specific score was good to excellent in 95 %, and 99 % of the fractures were radiologically healed.

Conclusion

The system is a versatile implant for proximal tibia fracture treatment. Polyaxiality and a specific locking mechanism are compatible with different fracture patterns. The minimally invasive technique effectively protects soft tissues but should not be performed at the expense of fracture reduction. Early functional results and complication rate are comparable to those in the literature.     

Implant Design Influences Tibial Post Wear Damage in Posterior-stabilized Knees

Background

The tibial post in posterior-stabilized total knees is a potential source of polyethylene wear debris, but the relationship between the shape and location of the tibial post in relation to the tibiofemoral bearing surfaces and the subsequent wear damage patterns remains unknown.

Questions/purposes

We used observations made on retrieved implant components from three contemporary posterior-stabilized knee designs to examine how differences in tibial post design affected wear damage on the post.

Methods

We examined 113 retrieved Zimmer NexGen^®, 103 Exactech Optetrak^®, and 58 Smith and Nephew Genesis^® II posterior-stabilized inserts using a subjective scale to grade post damage.

Results

All 274 inserts demonstrated wear damage. Total wear scores and scores for wear damage on the anterior post differed among designs: Optetrak^® 20 ± 4 and 5 ± 1, NexGen^® 13 ± 4 and 3 ± 1, and Genesis^® II 8 ± 3 and 1 ± 1, respectively. The Optetrak^® had predominantly anterior wear damage, the NexGen^® had more global wear damage, and the Genesis^® II had predominantly posterior wear damage. Tibial post wear damage and anterior post wear damage were primarily determined by implant design and to a lesser extent by length of implantation and revision diagnosis.

Conclusions

Although tibial post wear damage is multifactorial, the primary determinant of wear damage, and specifically anterior wear damage, is implant design.

Clinical Relevance

The constraint provided by the posterior-stabilized post-cam contact in modern knee arthroplasties is reflected in the wear damage patterns that occur during in vivo use. Unintended constraint such as anterior impingement should be addressed through design modifications for future posterior-stabilized knee arthroplasties.     

Open reduction and bi-columnar internal fixation of intra-articular distal humerus fractures through a combined medial and lateral approach

Purpose

The aim of this retrospective study was to investigate the suitability of bi-columnar internal fixation through a combined medial and lateral approach for the treatment of intra-articular distal humerus fractures.

Methods

Nineteen cases of intra-articular distal humerus fractures were treated with open reduction and bi-columnar internal fixation through a combined medial and lateral approach. The reduction in the articular surface and functional recovery of the affected elbows was assessed at an average follow-up of 15.8 ± 7.9 (7–43) months.

Results

The gap in the main articular fragments was less than 1 mm in 16 cases, while a gap of more than 1 mm and less than 2 mm was identified in 2 cases and of 3.7 mm in one case. All the fractures were united. At the latest follow-up, the mean flexion–extension of the elbows was 113.4° ± 20.7°, while the pronation–supination of the forearms was 158.3° ± 8.5°, and the mean Mayo Elbow Performance Index was 93.7 ± 9.1 points, leading to 13 excellent outcomes, and 6 with good results.

Conclusions

Intra-articular fractures of the distal humerus can be effectively treated by open reduction and internal fixation through a combined medial and lateral approach at the elbow.     

Single-incision technique for the internal fixation of distal fractures of the tibia and fibula: a combined anatomic and clinical study

Objectives

To present a novel single anterior-lateral approach for the treatment of distal tibia and fibula fracture via anatomical study and primary clinical application in order to minimize soft tissue complications.

Design

Both a gross anatomic cadaver and retrospective studies of the single-incision technique in patients recruited between June 2004 and January 2010.

Setting

Level I trauma center.

Patients/participants

Twenty-six legs of 14 adult human cadavers and clinical recruitment of 49 patients (29 males, 20 females) with a mean age of 37.6 years (range 11–68) with fracture of distal 1/3 tibia and fibula.

Intervention

A single anterior-lateral incision technique for open reduction and internal fixations of distal tibia and fibula fractures.

Main outcome measures

To identify the anatomic structures at risk in the anterolateral aspect of the lower leg and explicit the safe dissection distance from the extensor digitorum longus (EDL) to tibia and fibula, 26 legs of 14 adult human embalmed specimens were recruited in the anatomical study with the distance between the EDL and the anterior edge of the distal thirds of the tibia, as well as the distance between the EDL and the anterior edge of the distal thirds of the fibula were measured, and their mutual relationships to the surrounding anatomical structures described. Mean average standard deviations were also calculated. As for the clinical study, the quality of bone union and soft tissue healing were noted.

Results

The mean distances between the distal tibia and the EDL were measured to be 2.96 ± 0.46 cm (proximal), 1.85 ± 0.25 cm (middle), and 2.15 ± 0.30 cm (distal), and that between the fibula and the EDL were 1.82 ± 0.28 cm (proximal), 2.09 ± 0.31 cm (middle), and 2.30 ± 0.27 cm (distal), which means the safe gap from the distal tibia to EDL was1.6–3.4 cm and from the EDL to fibula was 1.5–2.6 cm. The anterior tibial vein and artery and the deep fibular nerve lie on the anterior interosseous membrane over the lateral surface of the distal tibia were excellently visualized. Review of clinical outcomes in 49 patients with combined distal tibial and fibular fractures who underwent reduction and fixation with the single-incision technique, revealed uneventful fracture healings in 47 patients; and two cases of superficial wound necrosis which were treated and healed in 4 months. There was no case of delayed union or non-union.

Conclusion

Distal fibula fracture occurring with distal tibia fracture poses a challenge for stable fixation. This has necessitated the need for dual incisions on the distal leg to approach each fracture for reduction and fixation. However, a single anterolateral incision enables the safe approach to the lateral aspects of the distal tibia and fibula thus eliminating the need for two separate incisions and minimizing the soft tissue complication to some extent. Meanwhile, the neurovascular bundle at risk during operation, distal tibia and fibula is clearly exposed in the single anterior-lateral incision.     

CT-based quantitative assessment of the surface size and en-face position of the coracoid block post-Latarjet procedure

Background

The success of shoulder stabilization with the Latarjet procedure might depend on the size of the bone graft and the positioning of the coracoid at the glenoid. The aim of this study was to quantitatively assess the surface of the coracoid bone graft and to assess its positioning in the en-face view.

Method

A series of 21 patients (17 men, 4 women, 26.1 ± 6.8 years—9 right, 12 left shoulders) were prospectively included and followed up with CT scans between December 2010 and April 2012 at an average of 2.4 ± 0.7 months postoperatively. The retrospective analysis of the CT scans was performed with Osirix? software. The coracoid surface was measured (cm²) in the sagittal plane. The positioning in relation to the center of the circumscribed circle of the glenoid was determined in the en-face clock face view of the glenoid.

Results

The grafts had a mean surface of 1.61 ± 0.51 cm² (mean ± standard deviation). The coracoid grafts were located between 01:05 hours (32.5°) and 05:33 hours (166.6°). Mean positioning was 02:00 hours (59.8° ± 16.1°) to 04:26 hours (133.0° ± 16.9°). The extent of the grafts was 73.2° ± 14.3°.

Discussion

The positioning of the coracoid graft on the clock face of the glenoid is situated in the decisive zone of 02:30–04:20 hours. The mean surface of the graft is smaller than expected from anatomical studies, but restores in defect situations bone stock in the potential defect areas at the anterior glenoid rim.

Level of evidence

Level IV, prospective case series, treatment study.     

Biomechanical comparison of different fixation techniques for reconstruction of tibial avulsion fractures of the anterior cruciate ligament

Purpose

The most common fixation techniques for tibial avulsion fractures of the anterior cruciate ligament (ACL) described in the literature are screw and suture fixation. The fixation of these fractures with the TightRope® device might be an alternative. Up to now it has been commonly used in other injuries, such as acromioclavicular joint or syndesmosis ruptures. The purpose of this study was to evaluate the biomechanical properties of different fixation techniques for the reconstruction of tibial avulsion fractures.

Methods

Type III tibial avulsion fractures were simulated in 40 porcine knees. Each specimen was randomly assigned to one of four groups: (1) anterograde screw fixation, (2) suture fixation, (3) TightRope® fixation or (4) control group. The initial displacement, strength to failure and the failure mode were documented.

Results

The maximum load to failure was 1,345?±?155.5 N for the control group, 402.5?±?117.6 N for the TightRope® group, 367?±?115.8 N for the suture group and 311.7?±?120.3 N for the screw group. The maximum load to failure of the control group was significantly larger compared to all other groups. The initial dislocation was 0.28?±?0.09 mm for the control group, 0.55?±?0.26 mm for the TightRope® group, 0.84?±?0.15 mm for the screw group and 1.14?±?0.9 mm for the suture group. The initial dislocation was significantly larger for the suture group compared to the TightRope® and control groups.

Conclusions

The TightRope® fixation shows significantly lower initial displacement compared to the suture group. The TightRope® fixation might be an alternative for the repair of ACL tibial avulsion fractures that can be used arthroscopically.     

Delayed ORIF of proximal humerus fractures at a minimum of 3 weeks from injury: a functional outcome study

Purpose

To evaluate the clinical results of open reduction and internal fixation (ORIF) in proximal humerus fractures with delayed presentation.

Design

Retrospective comparative study.

Setting

Level III.

Methods

From June 2005 to June 2010, thirty-nine (39) proximal humerus fractures were treated with ORIF after a delay of 21–120 days from the initial injury. Patients were divided into three groups: (1) isolated 2-part greater tuberosity fractures; (2) part surgical neck fractures; and (3) 3- and 4-part complex fractures. The range of motion (ROM), visual analogue scale (VAS), Constant–Murley score, University of California Los Angeles (UCLA) scoring system score and Simple Shoulder Test (SST) score were all recorded. The results were analyzed with the use of the Mann–Whitney U test and stratified by age, gender, side of injury, interval from injury to surgery, and postoperative functional results. Additionally, the results of different fracture types and complications were compared across the three groups.

Results

The mean forward flexion was 143.8° ± 28.9°, external rotation was 33.2° ± 19.6°, and internal rotation was up to the T10 level. The mean VAS was 0.8 ± 1.2; the mean Constant score was 82.0 ± 15.0; the UCLA score was 27.2 ± 7.1; and the mean SST was 9.5 ± 2.0 at the last follow-up. There were no significant differences among the three groups except in internal rotation. Compared to those without any complications, patients with complications demonstrated worse ROM and a lower functional score (p < 0.05).

Conclusions

Delayed treatment of proximal humerus fractures is a challenging problem. With appropriate surgical technique, satisfactory results can be expected with respect to different fracture types, and complications may be avoided regardless of delay.

Level of evidence

Therapeutic Level IV.     

Percutaneous Radiofrequency Epiphysiodesis in a Rabbit Model: A Pilot Study

Background

Techniques for epiphysiodesis have evolved from open surgical techniques requiring direct observation of the physis to percutaneous techniques performed with fluoroscopy.

Questions/purposes

Our purposes were to (1) describe a new minimally invasive surgical technique used to achieve epiphysiodesis using radiofrequency ablation, (2) document the effect of radiofrequency ablation on tibia length at 2, 6, and 12 weeks after ablation in a skeletally immature rabbit model, and (3) assess the effects of radiofrequency ablation on the histologic appearance of the proximal tibia physis and proximal tibia articular cartilage.

Materials and Methods

We performed epiphysiodesis of the rabbit proximal tibia on 15 skeletally immature male New Zealand White rabbits using a 22-gauge radiofrequency probe. The probe was positioned percutaneously and heated to 90°C for 4 minutes on the medial and lateral ½ of the physis. The opposite tibia was used as a control. Five animals were sacrificed at 2, 6, or 12 weeks postoperatively. Tibia length was compared using Faxitron® radiographs and electronic calipers. Histology of the growth plate was assessed with light microscopy.

Results

We observed differences in tibia length between 4.16 mm and 11.59 mm (average 7.86 mm) at 12 weeks. The proximal tibia physis closed radiographically and histologically in all animals by 12 weeks. Histologic analysis showed no evidence of articular cartilage injury.

Conclusions

This technique was reproducible and resulted in bone fusion of the rabbit proximal tibial growth plate. The use of radiofrequency ablation as described in this report may be used as an alternative to other surgical epiphysiodesis techniques.

Clinical Relevance

This technique may be useful for epiphysiodesis of small tubular bones of the hands and feet in humans.     

Osteosynthesis of distal radius fractures with the Micronail®

Introduction

The Micronail^® is a minimally invasive intramedullar titanium locking screw fixation for two-part dislocated extra-articular fractures and average displaced intra-articular fractures.

Patients and methods

In a retrospective study we analyzed the outcome of 20 distal radius fractures in 18 patients (17 female, mean age 78 years), which were treated by Micronail^®. Average follow-up time was 4 months. We describe the operative technique. All fractures were classified according to AO guidelines. We studied the radiologic and clinical outcome.

Results

According to the AO classification there were 12 A2, 3 A3, 1 B1, and 1 B3 fracture. Three patients had an antebrachii fracture. Mean American Society of Anesthesiologists (ASA) score was 2.4. Eight patients had associated lesions. Average operative time was 58 min. All fractures healed without major loss of alignment. There were two major complications: one patient developed a carpal tunnel syndrome and one device secondary dislocated. With the use of the Micronail^®, we found no infections or complications due to the insertion of the osteosynthesis materials. Patients experienced good to excellent results, on an analogue scale, in function of their wrist from the procedure. All patients had a good range of motion of the operated wrist; the difference between their two wrists was maximal 10° in all directions.

Conclusion

This intramedullary implant intends to minimize some of the disadvantages of other surgical options in the treatment of distal radius fracture; the Micronail^® causes less tissue damage and has early load-carrying capacity. This minimally invasive technique seems suitable in selected, two-part dislocated extra-articular and average displaced intra-articular, distal radius fractures.     

Total cervical disc replacement with the Discocerv® (Cervidisc Evolution) cervical prosthesis: early results of a second generation

Purpose

The purpose of the present study is to evaluate the early clinical and radiographic outcome in patients operated with Discocerv^® Cervidisc Evolution semi-constrained cervical mobile prosthesis (Discocerv^®), made of ceramic materials (Zirconia & Alumina).

Study design

This is a monocentric prospective noncomparative study.

Patient sample

Seventeen consecutive patients (8 men/9 women) were enrolled in the study so far. Mean age was 46.1 ± 7.9 years (33–62).

Methods

Patients in this series underwent one or two level total cervical disc replacement (TCDR) with Discocerv for disc herniation (n = 13), stenosis (n = 2) or discopathy (n = 1). Mean follow up was 4.8 ± 1.8 months (0–7.2).

Outcome measures

Clinical evaluation criteria included: VAS 1–100 mm self-reported cervical and radicular pain, neck disability index (NDI), symptoms evolution (ODOM score), work status, patient satisfaction index (PSI), mobility preservation. Prior to surgery VAS self-reported cervical and radicular pain were 62 mm (4–95) and 67 mm (2–96) respectively. NDI was 25/50 (9/50–37/50). Out of the active population (88%) 66% of patients were in sick leave for cervical symptoms. Radiographic criteria such as intervertebral mobility of the operated level were also assessed.

Results

Sixteen patients had a one level total cervical disc replacement (C3C4 n = 1, C4C5 n = 3, C5C6 n = 9, C6C7 n = 3. One patient had C5C6 and C6C7 total cervical disc replacement. Surgery duration was 67.1 ± 20.2 min (35–120). Hospital stay was 3.6 ± 1.5 days (2–7). No pre-operative or post-operative complications were reported in this series, except for excessive bleeding in one patient without any further consequences. About 47% of active patients resumed their previous work within the first 3 months after surgery. The ODOM score showed 100% excellent and good results. Three months post-operatively, mean VAS self-reported cervical and radicular pain decreased to 13 mm (0–60) and 5 mm (0–20) respectively and NDI decreased to 11/50 (0–24). All patients were satisfied with the results so far. Quantitative radiographic analysis showed satisfactory restoration of cervical mobility at the operated levels, with mean intervertebral mobility of 4.9° ± 5.6° (0 to 19.0°) in flexion-extension and 8.4° ± 4.1° (2.7°–16.9°) in lateral bending.

Conclusion

Early results with Discocerv^® Cervidisc Evolution cervical prosthesis are encouraging. However, further follow-up on a larger group is necessary to confirm these findings.     

Reduced loosening rate and loss of correction following posterior stabilization with or without PMMA augmentation of pedicle screws in vertebral fractures in the elderly

Background

Therapy of vertebral fractures in the elderly is a growing challenge for surgeons. Within the last two decades, the use of polymethylmethacrylate (PMMA) in the treatment of osteoporotic vertebral fractures has been widely established. Besides vertebroplasty and kyphoplasty, the augmentation of pedicle screws with PMMA found widespread use to strengthen the implant–bone interface. Several studies showed an enhanced pullout strength of augmented screws compared to standard pedicle screws in osteoporotic bone models. To validate the clinical relevance, we analyzed postoperative radiologic follow-up data in regard to secondary loss of correction and loosening of pedicle screws in elderly patients.

Materials and methods

In this retrospective comparative study, 24 patients admitted to our level I trauma center were analyzed concerning screw loosening and secondary loss of correction following vertebral fracture and posterior instrumentation. Loss of correction was determined by the bisegmental Cobb angle and kyphosis angle of the fractured vertebra. Follow-up computed tomography (CT) scans were used to analyze the prevalence of clear zones around the pedicle screws as a sign of loosening.

Results

In 15 patients (mean age 76 ± 9.3 years) with 117 PMMA-augmented pedicle screws, 4.3 % of screws showed signs of loosening, whereas in nine patients (mean age 75 ± 8.2 years) with 86 uncemented screws, the loosening rate was 62.8 %. Thus, PMMA-augmented pedicle screws showed a significantly lower loosening rate compared to regular pedicle screws. Loss of correction was minimal, despite poor bone quality. There was significantly less loss of correction in patients with augmented pedicle screws (1.1° ± 0.8°) as compared to patients without augmentation (5° ± 3.8°).

Conclusion

The reinforcement of pedicle screws using PMMA augmentation may be a viable option in the surgical treatment of spinal fractures in the elderly.     

Reamed intramedullary nailing of diaphyseal tibial fractures: comparison of compression and non-compression nailing

Background

Modern intramedullary implants provide the option to perform compression at the fracture gap in long bone fractures via a compression screw mechanism. The aim of this study was to assess if the application of interfragmentary compression in the intramedullary nailing of tibia fractures could increase the union rate and speed of fracture healing.

Methods

Sixty-three patients who suffered from an AO-type 42-A3 or 42-B2 fracture that was treated by reamed intramedullary nailing between 2003 and 2008 were included in this retrospective study. Twenty-five patients were treated with dynamic interlocking without compression while 38 were treated with compression nailing. The compression load of the dynamic proximal screw was calculated by postoperative X-ray and radiographs taken four weeks after operation. Healing was assessed by radiological evaluation until the completion of bony healing or the disappearance of clinical symptoms. Nonunion was defined as the absence of radiological union and the persistence of clinical symptoms after six months.

Results

Postoperative compression was applied at a mean load of 1,852 N, and 980 N remained after four weeks. In the compression group, 19 open and 19 closed fractures occurred. In the non-compression group, 25 patients were included (14 closed and 11 open cases). Active compression decreased healing time significantly. Nonunion occurred in one compression patient and three non-compression patients.

Conclusion

The results show that additional compression of the fracture gap can improve healing outcome in simple transverse tibial shaft fractures treated with reamed nailing.     

Exakte Messung des Volumeneffektes von 6%iger Hydroxyethylstärke 130/0,4 (Voluven®) während präoperativer akuter normovolämer Hämodilution

Background

What is the effect of preoperative acute normovolemic hemodilution (ANH) with 6% hydroxyethyl starch (HES) 130/0.4 (Voluven^®) on blood volume?

Methods

In 10 patients undergoing radical hysterectomy, ANH was performed to a hematocrit of 21% using 6% HES 130/0.4 (Voluven^®) whereby a replacement of blood with 115% of colloid was planned. Plasma volume (indocyanine green dilution technique) and hematocrit were determined before, 30 and 60 min after ANH. Red cell volume (labelling erythrocytes with fluorescein) was determined before and 30 min after ANH.

Results

After removal of 1,431±388 ml of blood and simultaneous replacement with 1,686±437 ml of colloid, blood volumes were 218±174 ml higher than before (at 105±4%). The volume effect was 98±12%, 30 min after ANH. Even 60 min after ANH, mean blood volumes were with 4,228±986 ml slightly higher than before ANH (102±5%). The hematocrit decreased disproportionally in relation to the residual intravascular volume. Consequently, estimating the volume effect from the changes in hematocrit led to an overestimation (about +30%).

Conclusion

Double label measurements of blood volume demonstrated that the volume effect of 6% HES 130/0.4 (Voluven^®) is about 100% in the course of ANH. The reason for the disproportionally large decrease in hematocrits could be the mobilization of a fraction of the plasma volume which was retained within the endothelial glycocalyx.     

Clinical outcome following the first-line, single lesion microfracture at the knee joint

Study design

Case series: Level of evidence, 4.

Background

Arthroscopic microfracture of chondral defects across the knee joint is a frequent treatment modality. There is only limited information on the clinical outcome in patients without previous surgery and single lesions.

Purpose

Evaluation of clinical outcome following microfracture in patients without previous surgery and single lesions and identification of prognostic factors.

Methods

Inclusion criteria were patients with single-lesion knee joint first-line microfracturing at minimum 2 years postoperatively. Charts were reviewed to identify patient and defect characteristics. Clinical outcome was evaluated by IKDC and Lysholm knee scores, Tegner activity scale and a numeric analogue scale (NAS) for function and pain (10 = highest possible function, no pain).

Results

Totally, 145 patients (age at operation 47.92 ± 15.7) met inclusion criteria. Average defect size was 2.7 ± 1.9 cm². Postoperatively, IKDC was 73.1 ± 18.5, Lysholm 77.6 ± 19.1, Tegner 4.5 ± 1.7, NAS pain 6.5 ± 2.6 and NAS function 6.4 ± 2.3. Significantly better clinical outcome was observed in male patients than in female patients. Regression analysis including all patient and defect characteristics highlighted that singly the parameter shorter symptom duration (P = 0.018) significantly predicted an improved postoperative clinical outcome.

Conclusion

Microfracturing results in a satisfying clinical outcome, but no full recovery in patients without previous surgery and single lesions. Specific parameters facilitate outcome prognosis and therefore may aid in indicating surgery.     

Association of facet tropism and progressive facet arthrosis after lumbar total disc replacement using ProDisc-L®

Purpose

The purpose of this retrospective study was to examine the association of facet tropism and progressive facet arthrosis (PFA) after lumbar total disc replacement (TDR) surgery using ProDisc-L^®.

Methods

A total of 51 segments of 42 patients who had undergone lumbar TDR using ProDisc-L^® between October 2003 and July 2007 and completed minimum 36-month follow-up period were retrospectively reviewed. The changes of facet arthrosis were categorized as non-PFA and PFA group. Comparison between non-PFA and PFA group was made according to age, sex, mean follow-up duration, grade of preoperative facet arthrosis, coronal and sagittal prosthetic position and degree of facet tropism. Multiple logistic regression analysis was also performed to analyze the effect of facet tropism on the progression of facet arthrosis.

Results

The mean age at the surgery was 44.43 ± 11.09 years and there were 16 males and 26 females. The mean follow-up period was 53.18 ± 15.79 months. Non-PFA group was composed of 19 levels and PFA group was composed of 32 levels. Age at surgery, sex proportion, mean follow-up period, level of implant, grade of preoperative facet arthrosis and coronal and sagittal prosthetic position were not significantly different between two groups (p = 0.264, 0.433, 0.527, 0.232, 0.926, 0.849 and 0.369, respectively). However, PFA group showed significantly higher degree of facet tropism (7.37 ± 6.46°) than that of non-PFA group (3.51 ± 3.53°) and p value was 0.008. After adjustment for age, sex and coronal and sagittal prosthetic position, multiple logistic regression analysis revealed that facet tropism of more than 5° was the only significant independent predictor of progression of facet arthrosis (odds ratio 5.39, 95 % confidence interval 1.251–19.343, p = 0.023).

Conclusions

The data demonstrate that significant higher degree of facet tropism was seen in PFA group compared with non-PFA group and facet tropism of more than 5° had a significant association with PFA after TDR using ProDisc-L^®.