Cationised gelatin and hyaluronic acid coating enhances polyethylene terephthalate artificial ligament graft osseointegration in porcine bone tunnels

Purpose

The aim of this study was to investigate whether cationised gelatin and hyaluronic acid (CH) coating could induce polyethylene terephthalate (PET) artificial ligament graft osseointegration in the bone tunnel.

Methods

Surface modification of PET artificial ligament graft was performed by layer-by-layer (LBL) self-assembly CH coating. Six pigs underwent anterior cruciate ligament (ACL) reconstruction on the right knees, with three pigs receiving the CH-coated PET grafts and the other three pigs non-CH-coated PET grafts as controls. They were sacrificed at three months after surgery and the graft-bone complexes were acquired for computed tomography (CT) scan and histological examination.

Results

CT scans showed a significant difference at the distal femoral site (p = 0.031) or at the distal tibial site (p = 0.0078), but no significant difference in the bone tunnel areas’ enlargement at other sites (p > 0.05) between the CH group and the control group. Histologically, application of CH coating induced new bone formation between graft and bone at three months compared with the controls at the distal site. The interface width of the CH group was significantly lower than that of the control group at the distal femoral site (p = 0.0327) and at the distal tibial site (p = 0.0047).

Conclusions

The study has shown that CH coating on the PET artificial ligament surface has a positive biological effect in the induction of artificial ligament osseointegration within the bone tunnel at the distal site of the bone tunnel.     

Osseointegration of polyethylene implants coated with titanium and biomimetically or electrochemically deposited hydroxyapatite in a rabbit model

Purpose

The aim of this study was to evaluate the osseointegration of a new coating directly deposited on PE at room temperature.

Methods

Thirty-six (36) male New Zealand rabbits were randomly assigned to receive one out of three types of implants: two tested implants, i.e. PE implant coated with TiPVD and biomimetic HA (biomimetic), PE implant coated with TiPVD and electrolytic HA (electrolytic), and positive control made of massive microrough titanium coated with plasma sprayed HA (TiHAPS). Osseointegration was evaluated by histomorphometry (bone tissue in contact [BIC]), mineralized bone area [MBA]) and mechanical testing (push-out test, interfacial shear strength [ISS]) at six and 12 weeks in the distal femurs.

Results

For BIC there were no differences between the groups at six (p = 0.98) and 12 weeks (p = 0.13). For MBA, no statistically significant difference was measured between groups at six (p = 0.52) and 12 weeks (p = 0.57). At six weeks, interfacial shear strength (ISS) was significantly higher (p = 0.01) for TiHAPs implants compared to biomimetic and electrolytic implants. This difference was not significant at 12 weeks (p = 0.92).

Conclusion

The osseointegration of biomimetic and electrolytic implants was equivalent to a positive control at 12 weeks.     

A radiographic and clinical comparison of reamer–irrigator–aspirator versus iliac crest bone graft in ankle arthrodesis

Purpose

We evaluated radiographic fusion at follow-up and complication rates in patients who had either iliac crest (ICBG) or femoral reamer–irrigator–aspirator (RIA) bone graft for tibiotalar fusion.

Methods

We retrospectively reviewed charts and radiographs of all patients who had a tibiotalar fusion from August 2007 to February 2011. Records were analysed for patient demographics, complications, and clinical symptoms. Radiographs were reviewed in sequential order by two fellowship-trained foot and ankle surgeons and one orthopaedic surgeon who specialises in foot and ankle surgery to determine radiographic fusion at routine follow-up. Patients were contacted to determine current visual analog scores (VAS) at their graft site.

Results

Mean patient age was 49.4 ± 12.1 years in the RIA group and 49.3 ± 15.4 years in the ICBG group (p = .97). Pre-operative characteristics showed no significant differences between groups. The ICBG group had significantly more nonunions than the RIA group (six vs. one, p = 0.04). Two patients in the ICBG had chronic pain at their graft site based on their VAS score; there were none in the RIA group. Radiographic fusion at follow-up was similar between groups, with no significant difference (12.48 ± 3.85 weeks vs.12.21 ± 3.19 weeks, p = .80).

Conclusions

There was a significantly higher nonunion rate in the ICBG group, but both groups had a solid radiographic bony fusion at similar follow-up time points. Our results suggest RIA bone graft is a viable alternative to ICBG for tibiotalar fusion.     

Improved outcomes after anterior cruciate ligament reconstruction with quadrupled hamstring autografts and additional bone plug augmentation at five year follow-up

Purpose

Hybrid fixation has been proposed to improve outcomes of anterior cruciate ligament (ACL) reconstructions. This study evaluated midterm outcomes after transfemoral graft fixation using either a conventional or a modified technique using additional bone plug augmentation (BPA) of the femoral tunnel aperture.

Methods

Seventy-one consecutive patients undergoing ACL reconstruction using a quadrupled hamstring autograft with transfemoral graft fixation and tibial interference screw fixation were included. Of these, 56 patients could be followed up 61 months (range 52–69 months) after ACL reconstruction both clinically and by magnetic resonance imaging (group A, conventional technique, n = 34; group B, modified technique, n = 22). Anteroposterior (AP) laxity measurements and International Knee Documentation Committee (IKDC), Lysholm and Tegner activity scoring were performed, while imaging included assessment of bone tunnel diameters, graft condition and graft filling at the femoral bone tunnel aperture.

Results

Patients with additional BPA had a significantly higher degree of graft filling at the femoral bone tunnel aperture (p = .0135) and ‘healthier’ grafts (p = .0495). They also tended to display less AP laxity difference in terms of mean differences and total patient numbers. Lysholm, IKDC and Tegner activity index scores and bone tunnel diameters were not significantly different.

Conclusions

Additional BPA is an easy-to-perform, cheap and safe manoeuvre, which has the capacity to improve morphological and clinical outcomes at five year follow-up. However, femoral tunnel widening is unaffected by additional BPA.     

Outcomes after shoulder arthroplasty revision with glenoid reconstruction and bone grafting

Purpose

Extensive glenoid bone loss after failed shoulder arthroplasty represents a challenge for revision arthroplasty. Treatment options vary widely and have been a source of controversy among experts.

Methods

Between 2004 and 2010, a total of 17 patients underwent glenoid reconstruction surgery using an autologous iliac crest bone graft and secondary revision arthroplasty due to extensive glenoid bone loss after failed previous total shoulder arthroplasty. The outcomes were assessed by means of clinical examination, Constant score, and bi-plane radiography as well as pre-, postoperative and follow-up CT.

Results

Before the revision surgery, the mean Constant score was 24 ± 17 and improved to 40 ± 13 after the glenoid rebuilding and revision arthroplasty. CT imaging revealed adequate glenoid bone stock restoration with no relevant graft resorption or loosening of the glenoid. The average postoperative antero-posterior diameter of the glenoid was 28 ± 3 mm which had decreased to 25 ± 3 mm at follow-up. The average postoperative version of the glenoid was 95.7° ± 6° and had decreased to 98.5° ± 4° at follow-up. Both the glenoid version and diameter had changed significantly (P < 0.001) comparing postoperative and follow-up CT-scans.

Conclusion

Glenoid reconstruction surgery using an iliac crest bone-block autograft prior to revision arthroplasty represents a valuable salvage procedure in cases of extensive glenoid bone loss after primary shoulder arthroplasty. Sufficient glenoid bone stock restoration is indispensable for reliable fixation of glenoid components and in turn a satisfactory clinical outcome.     

Anterior cruciate ligament deficiency leads to early instability of scaffold for cartilage regeneration: a controlled laboratory ex-vivo study

Purpose

The affect of anterior cruciate ligament (ACL) integrity on the early postoperative stability of a collagen type-I gel scaffold was investigated. The value of fibrin glue for graft fixation in ACL deficient porcine knees over a simulated early postoperative period was also studied.

Methods

Full-thickness articular cartilage defects (11 × 6 mm) were created on the medial femoral condyle of 80 porcine knees. The ACL was left intact or completely transected in each of 40 knees. Gel plugs were tested in each group: press-fitting only in 20 specimens and press-fitting plus fibrin glue in 20 specimens. Each knee underwent 2,000 cycles in a validated ex-vivo continuous passive motion model.

Results

Press-fit-only fixation grafts in knee specimens with an intact ACL showed significantly superior stability than that in ACL deficient knees (p = 0.01). In ACL deficient knees, grafts fixed with press-fitting plus fibrin glue showed significantly superior stability than those using press-fit only fixation (p = 0.01). Press-fitting plus fibrin glue fixation showed no significant differences in worn surface area between knee specimens with intact and deficient ACL.

Conclusions

ACL deficiency led to early scaffold instability in an ex-vivo porcine knee model. Fibrin glue in ACL deficient knees led to additional graft stability. These findings indicated that cartilage regenerative techniques may give optimum results in ACL intact knees.     

Prosthetic radial head stem pull-out as a mode of failure: a biomechanical study

Purpose

Press-fit cementless radial head implant longevity relies on adequate bone ingrowth. Failed implant osseointegration remains a clinical concern and has been shown to lead to prosthetic failure. The purpose of this study was to test the hypothesis that implants with sufficient initial press-fit stability would be less likely to fail due to implant pull-out, as demonstrated by an increasing amount of energy required to remove the prosthesis from the canal.

Methods

Ten cadaveric radii were implanted with five sizes (6–10 mm in 1-mm increments) of grit-blasted, cementless radial head stems. A customised slap hammer was used to measure the energy required to remove each stem. Stem-bone micromotion was also measured.

Results

The suboptimally sized stem (Max − 1) (i.e. 1 mm undersized) required less energy (0.5 ± 0 J) to pull out than the optimally sized stem (Max) (1.7 ± 0.3 J) (p = 0.008). The optimally sized stem demonstrated greater initial stability (45 ± 7 μm) than the suboptimally sized stem (79 ± 12 μm) (p = 0.004).

Conclusions

This investigation demonstrates the importance of obtaining adequate press-fit stability for the prevention of radial head stem pull-out failure. These data add to the relatively scant knowledge in the literature regarding radial head biomechanics. The energy required to remove a prosthetic radial head ingrowth stem decreases in conjunction with diameter. The use of an inadequately sized stem increases the stem’s micromotion as well as the risk of prosthetic loosening due to pull-out.     

Repair of segmental long-bone defects by stem cell concentrate augmented scaffolds: a clinical and positron emission tomography - computed tomography analysis

Purpose

Treating segmental long-bone defects remains a major challenge. For defects >3 cm, segmental transport represents the gold standard, even though the method is time consuming and afflicted with several complications. The aim of this study was to evaluate healing of such defects after grafting an osteogenic scaffold previously seeded with stem cell concentrate.

Methods

We evaluated five patients with segmental long-bone defects (3–14 cm) treated with bone marrow aspirate concentrates (BMAC) seeded onto a bovine xenogenous scaffold. The healing process was monitored by X-rays and positron emission tomography–computed tomography (PET-CT) three months after surgery.

Results

Centrifugation led to a concentration of leukocytes by factor 8.1 ± 7.5. Full weight bearing was achieved 11.3 ± 5.0 weeks after surgery. PET analysis showed an increased influx of fluoride by factor 8.3 ± 6.4 compared with the contralateral side (p < 0.01). Bone density in the cortical area was 75 ± 16 % of the contralateral side (p < 0.03). The patient with the largest defect sustained an implant failure in the distal femur and finally accomplished therapy by segmental transport. He also had the lowest uptake of fluoride of the patient collective (2.2-fold increase).

Conclusion

Stem cell concentrates can be an alternative to segmental bone transport. Further studies are needed to compare this method with autologous bone grafting and segmental transport.     

Behaviour of the ultra-short anatomic cementless femoral stem in young and elderly patients

Purpose

The question arises as to whether it is possible to obtain rigid fixation of the ultra-short metaphyseal-fitting anatomic cementless stem without diaphyseal fixation in the elderly as well as younger patients. We investigated whether ultra-short, metaphyseal-fitting anatomic cementless femoral stem would provide similar functional improvements in the younger and elderly patients, radiographically secure implant fixation would be achieved in both groups, the bone content would be preserved in both groups, and complication rates would be similar in both groups.

Methods

A total of 100 patients (114 hips) in the younger patient group and 100 patients (112 hips) in the elderly patient group were included in the study. Their mean age was 43.9 ± 6.11 years (range, 31–65 years) in the younger patient group and 78.9 ± 12.1 years (range, 66–91 years) in the elderly patient group. The mean duration of follow-up was 7.5 years (range, six to nine years) in the younger patient group and 7.6 years (range, six to nine years) in the elderly patient group.

Results

The mean postoperative Harris hip scores (95 points versus 91 points), WOMAC scores (11 points versus 15 points), thigh pain (none in either group), UCLA activity scores (6.5 points versus 4.5 points), and radiographic results were not significantly different between the two groups. No hip in either group had an aseptic loosening. No hip in either group had clicking or squeaking sounds or ceramic fractures.

Conclusion

The cementless ultra-short, metaphyseal-fitting anatomic cementless femoral component provides stable fixation without any need of diaphyseal fixation in both younger and elderly patients. Despite the concern, the poor bone quality in elderly patients did not compromise the stability, and osseointegration of this ultra-short, anatomic cementless femoral stem was achieved in all elderly patients.     

Direct subcutaneous injection of polyethylene particles over the murine calvaria results in dramatic osteolysis

Purpose

The murine calvarial model has been widely employed for the in vivo study of particle-induced osteolysis, the most frequent cause of aseptic loosening of total joint replacements. Classically, this model uses an open surgical technique in which polyethylene (PE) particles are directly spread over the calvarium for the induction of osteolysis. We evaluated a minimally invasive modification of the calvarial model by using a direct subcutaneous injection of PE particles.

Methods

Polyethylene (PE) particles were injected subcutaneously over the calvaria of C57BL6J ten-week-old mice (“injection” group) or were implanted after surgical exposure of the calvaria (“open” group) (n = 5/group). For each group, five additional mice received no particles and served as controls. Particle-induced osteolysis was evaluated two weeks after the procedure using high-definition microCT imaging.

Results

Polyethylene particle injection over the calvaria resulted in a 40 % ± 1.8 % decrease in the bone volume fraction (BVF), compared to controls. Using the “open surgical technique”, the BVF decreased by 16 % ± 3.8 % as compared to controls (p < 0.0001).

Conclusions

Direct subcutaneous injection of PE particles over the murine calvaria produced more profound resorption of bone. Polyethylene particle implantation by injection is less invasive and reliably induces osteolysis to a greater degree than the open technique. This subcutaneous injection method will prove useful for repetitive injections of particles, and the assessment of potential local or systemic therapies.     

Ilizarov non-free bone plasty for extensive tibial defects

Purpose

The purpose of this study was to present a retrospective comparative overview of the Ilizarov non-free bone plasty techniques of one-stage multilevel fragment lengthening and gradual tibilisation of the fibula used for extensive tibial defect management.

Methods

Extensive tibial defects in 83 patients were managed either by multilevel fragment lengthening (group I, n = 41, mean defect size 13.1 ± 0.9 cm) or gradual tibilisation of the fibula (group II, n = 42, mean defect size 12.5 ± 1.2 cm) using the Ilizarov apparatus. The initial findings, treatment protocols and outcomes of those patients treated within the period 1972–2011 were studied retrospectively by medical records and radiographs, and statistically assessed with Microsoft Excel and Attestat software.

Results

Group I had multilevel fragment lengthening over one stage that averaged 288.0 ± 14.4 days. The mean total period of gradual tibilisation of the fibula in group II was 316.0 ± 29.7 days. The patient’s age in the latter group had an effect on the completeness of leg-length equalisation.

Conclusions

The techniques can be used to manage extensive tibial defects as all the defects bridged, leg-length discrepancy and deformity were corrected and patients were able to load their limbs.     

A prospective study to assess the outcomes of revision anterior cruciate ligament reconstruction

Purpose

Continuously increasing numbers of primary anterior cruciate ligament (ACL) reconstructions invites a parallel increase in graft failures and need for revision ACL reconstruction surgery. High failure rates has previously stigmatised the revision surgery. We performed this study using multiple outcome measures together with clinical examination to offer a full assessment of the outcomes of this procedure.

Methods

Twenty patients, with mean age of 29.4 years (17–50 years), were included in this study prior to their revision ACL reconstruction surgery. All patients were followed prospectively collecting the Knee injury and Osteoarthritis Outcome (KOOS), International Knee Documentation Committee (IKDC) and Tegner-Lysholm scores pre- and post-operatively together with clinical assessment of the antero-posterior knee laxity.

Results

After a mean follow up interval of 30 months (16–60 months) significant post-operative improvement of IKDC, Tegner-Lysholm scores and knee antero-posterior laxity together with the Symptoms, Activities of Daily Living (ADL) and Quality of Life (QOL) components of the KOOS score was noticed (P < 0.05). However, there was no similar improvement in pain and sports components of the KOOS score (P > 0.05). There was no difference in the outcomes of different graft types.

Conclusion

Good outcomes of revision ACL reconstruction surgery are achievable. The use of different graft types did not affect the outcome of the procedure. Most of the patients opted to less aggressive sports participation after the revision procedure.     

A new strategy to enhance artificial ligament graft osseointegration in the bone tunnel using hydroxypropylcellulose

Purpose

The aim of this study was to determine whether hydroxypropylcellulose (HPC) coating of polyethylene terephthalate (PET) artificial ligaments enhances graft osseointegration in the bone tunnel.

Methods

Thirty New Zealand white rabbits underwent artificial ligament graft transplantation in the bilateral proximal tibia tunnels. One limb was implanted with an HPC-coated PET graft, and the contralateral limb was implanted with a non-HPC-coated PET graft as a control. The rabbits were then randomly sacrificed at weeks four and eight after surgery for biomechanical testing, histological examination, and histomorphometric and real-time polymerase chain reaction analysis.

Results

At week four after surgery, there were no statistically significant differences in the load to failure or stiffness values between the experimental and control limbs (P = 0.328 and P = 0.128, respectively). At week eight after surgery, the mean load to failure and stiffness value of the experimental limbs was higher than that of the control limbs (P < 0.001 and P = 0.018, respectively). At week eight after surgery, some protruding new bone tissue from the host bone to the graft was found in the HPC-coated group, while a thick fibrous tissue band was observed at the interface between the graft and the host bone in the control group. Histomorphometric analysis showed that the graft-bone interface width in the HPC-coated group was significantly narrower than that in the control group at week eight after surgery (P < 0.001). At weeks four and eight after surgery, the mRNA expression level of bone morphogenetic protein-2 in the HPC group was higher than that in the control group (P = 0.001 and P = 0.010, respectively). The mRNA expression level of osteopontin in the HPC group was higher than that in the control group only at week four after surgery (P = 0.032).

Conclusions

Our data show that an HPC coating on the surface of PET artificial ligament grafts may induce artificial ligament graft osseointegration in the bone tunnel.     

Comparison of low, multidirectional locked nailing and plating in the treatment of distal tibial metadiaphyseal fractures

Purpose

The aim of this study was to compare the results of a new technique for low, multidirectional locked nailing with closed reduction and minimally invasive plating in the treatment of distal tibial metadiaphyseal fractures.

Methods

Forty-six matched patients were divided according to age, gender, Injury Severity Score, and fracture pattern into group A (expert tibial nailing) and group B (minimally invasive plating). Then, the patients were followed up, and the clinical and radiographic results were retrospectively analysed.

Results

The mean followed-up was 24.7 ± 2.7 months in group A and 25.8 ± 2.8 months in group B. No patient had nonunion, shortening, hardware breakdown, or deep-seated infection. Patients in group A had a significantly shorter mean operating time, hospital stay, full weight-bearing time and union time (76 ± 16.6 vs. 90 ± 20.3 minutes, p = 0.000; 5.8 ± 2.1 vs. 8.9 ± 3.1 days, p = 0.000; 9.0 ± 1.4 vs. 11.1 ± 1.7 weeks, p = 0.000; and 21.3 ± 3.5 vs. 23.1 ± 3.6 weeks, p = 0.047, respectively). Three patients in group A and one patient in group B presented with malalignment (p = 0.608). The mean Olerud-Molander Ankle score was 89.0 ± 7.1 in group A and 87.6 ± 8.4 in group B (p = 0.478).

Conclusions

Distal tibia metadiaphyseal fractures may be treated successfully with low, multidirectional locked nails or plates. However, low, multidirectional locked nailing may represent a superior surgical option, since it offers advantages in terms of mean operating time, hospital stay, full weight-bearing time and union time.     

Poorer survival after a primary implant during revision total knee arthroplasty

Purpose

Revision total knee arthroplasty (rTKA) is a complex procedure. Depending on the degree of ligament and bone damage, either primary or revision implants are used. The purpose of this study was to compare survival rates of primary implants with revision implants when used during rTKA.

Methods

A retrospective comparative study was conducted between 1998 and 2009 during which 69 rTKAs were performed on 65 patients. Most common indications for revision were infection (30 %), aseptic loosening (25 %) and wear/osteolysis (25 %). During rTKA, a primary implant was used in nine knees and a revision implant in 60.

Results

Survival of primary implants was 100 % at one year, 73 % [95 % confidence interval (CI) 41–100] at two years and 44 % (95 % CI 7–81) at five years. Survival of revision implants was 95 % (95 % CI 89–100) at one year, 92 % (95 % CI 84–99) at two years and 92 % (95 % CI 84–99) at five years. Primary implants had a significantly worse survival rate than revision implants when implanted during rTKA [P = 0.039 (hazard ratio = 4.56, 95 % CI 1.08–19.27)].

Conclusions

Based on these results, it has to be considered whether primary implants are even an option during rTKA.     

Enhanced migration of human bone marrow stromal cells in modified collagen hydrogels

Purpose

Collagen I hydrogels are widely used as scaffolds for regeneration of articular cartilage defects. We hypothesised that ingrowth might be improved by removing the superficial layer of a compressed hydrogel. The control group consisted of the original unmodified product.

Methods

The migration of human bone marrow stromal cells (hBMSCs) into the hydrogel was evaluated by confocal microscopy. We quantified the DNA concentration of the hydrogel for each group and time point and evaluated the chondrogenic differentiation of cells.

Results

After one week, the detectable amount of cells at the depth of 26–50 μm was significantly higher in the modified matrix (MM) than in the non-modified matrix (NM) (p = 0.011). The maximum depth of penetration was 75 μm (NM) and 200 μm (MM). After three weeks, the maximum depth of penetration was 175 μm (NM) and 200 μm (MM). Likewise, at a depth of 0–25 μm the amount of detectable cells was significantly higher in the MM group (p = 0.003). After 14 days, the concentration of DNA was significantly higher in the samples of the MM than in the control group (p = 0.000). Staining of histological sections and labelling with collagen II antibodies showed that a chondrogenic differentiation of cells in the scaffold can occur during in vitro cultivation.

Conclusions

Removing the superficial layer is essential to ensuring proper ingrowth of cells within the compressed hydrogel. Compressed hydrogels contribute better to cartilage regeneration after surface modification.     

Role of the mechanical axis of lower limb and body weight in the horizontal tear and root ligament tear of the posterior horn of the medial meniscus

Purpose

To compare and analyse the relationship between horizontal tear and root ligament tear of the posterior horn of the medial meniscus (PHMM) and the degree of varus in the axis of lower limb and body weight.

Methods

One hundred and nineteen patients underwent surgical treatment as they were diagnosed with medial meniscus tear in our hospital from May 2006 to December 2009. Of these, 19 cases (group 1), underwent partial meniscectomy as they were confirmed to solely have horizontal tear of the PHMM on arthroscopic examination and 27 cases (group 2), underwent subtotal meniscectomy as they were confirmed to solely have root ligament tear of the PHMM on arthroscopic examination, were chosen for retrospective study. Standing radiographs were taken of every case prior to arthroscopic surgery to measure varus angle. Also, we checked body mass index (BMI) of two groups. The difference of varus angle and BMI between two groups were statistically verified using the Levene’s test, paired t-test.

Results

Group 1 showed mean value of varus angle of 2.30 ± 0.54, and BMI of 25.32 ± 3.23. Group 2 showed mean value of varus angle of 5.64 ± 0.54, and BMI of 25.67 ± 3.12. The degree of varus of group 2 was statistically significantly higher than group 1 (p = 0.002). Comparison between the BMI of two groups showed no statistical significance (p = 0.053).

Conclusion

Through a comparative study of sole horizontal tear and root ligament tear of the PHMM, the authors have found that sole root ligament tear of the PHMM is more relative to the genu varum than sole horizontal tear of the PHMM. However, body weight was statistically irrelevant to the incidence of the two lesions.     

Incidence and management of hip dislocation in tumour patients with a modular prosthesis of the proximal femur

Purpose

Little data is available about the incidence and especially the management of hip dislocation following the implantation of modular tumor prostheses of the proximal femur. In this retrospective single-centre study we assessed the incidence of hip dislocation following implantation of a proximal femoral modular prosthesis as well as the success of the subsequent surgical or non-surgical treatment in tumor patients.

Methods

Between 1982 and 2008, 166 tumor patients received a modular prosthesis of the proximal femur at our institution. The average age at the time of surgery was 50 ± 20 years (range, six to 84 years). An additional pelvic reconstruction was done in 14 patients. An artificial band for soft tissue reconstruction of the hip was used in 19 patients. The average time of follow-up was 46 ± 64 months (range, one to 277 months).

Results

The overall dislocation rate after proximal femoral replacement was 13 % after a mean time of seven ± eight months (range, 0.3–33 months) after surgery. Between 1982 and 1986 the dislocation rate was 33 % and declined to 9 % in subsequent years (1987–2008). Patients who had received an additional pelvic reconstruction had a three fold higher dislocation rate (p <0.05). Patients with closed reduction had a 58 % (eight of 12) re-dislocation rate compared to 11 % (one of nine) for open reduction (p = 0.0357).

Conclusions

Dislocation of a modular prosthesis of the proximal femur is a common complication, especially in cases with additional pelvic resection with extensive bone and soft-tissue defects. Open surgical management may be more effective in preventing re-dislocation than closed reduction and bracing alone.     

Extra-articular dorsal closing-wedge osteotomy to treat late-stage Freiberg disease using polyblend sutures: technical tips and clinical results

Purpose

The purpose of this study was to evaluate the clinical outcomes regarding the dorsal wedge osteotomy fixed using a polyblend suture and describe the usefulness of this fixation method for the treatment of Freiberg disease.

Methods

The subjects consisted of 13 feet from 13 cases suffering from Freiberg disease that underwent extra-articular dorsal closing-wedge osteotomy using a polyblend suture. The average age was 31.7 (range 13–72) years. The average follow-up period was 17 (range 14–24) months. Regarding image findings, time to bone union and metatarsal shortening was reviewed. The investigation was carried out using the range of motion (ROM), visual analog scale (VAS), and Japanese Society of the Surgery of Foot lesser toe scale (JSSF score) in the MTP joint before surgery and at the latest follow-up.

Results

Calluses under the metatarsal head were not observed in any cases. The mean metatarsal shortening was 2.33 ± 2.07 mm at follow-up. The bone union required an average of 8.4 ± 0.8 weeks. The average ROM of dorsal flexion improved from 37.2 ± 5.3° before surgery to 73.6 ± 9.9° at latest follow-up (p < 0.0001). The average ROM of plantar flexion improved from 16.0 ± 10.1° before surgery to 19.5 ± 8.6° at latest follow-up (p = 0.35). The average VAS significantly improved from 75.3 ± 8.5 before surgery to 4.9 ± 4.2 at latest follow-up (p < 0.0001). The average JSSF score significantly improved from 67.3 ± 9.4 points before surgery to 98.8 ± 3.0 points at the latest follow-up (p < 0.0001).

Conclusion

Extra-articular dorsal closing-wedge osteotomy using a polyblend suture was carried out to treat Freiberg disease. The bone union was observed in all cases with improved clinical results. Fixation using a polyblend suture was considered to be useful.     

Atypical femoral fractures after anti-osteoporotic medication: a Korean multicenter study

Purpose

Increasing numbers of atypical femoral fractures have been reported among long-term bisphosphonate users. We evaluated clinical characteristics of atypical femoral fractures throughout Korean multicenter studies.

Methods

We retrospectively analysed the bone mineral density, prodromal symptoms before femoral fracture, and medication history of osteoporosis in 76 cases of atypical femoral fracture.

Results

The mean age of cases was 71.4 ± 8.8 (range, 43–89) years old. The mean follow-up period after the fracture operation was 24.5 ± 12.9 (range, 12–79) months. BMI was 23.2 ± 3.0 on average. The mean BMD of femur was −1.9 ± 1.4 (range, −4.8 to 1.3). Prodromal symptoms including thigh pain before femoral fracture appeared in 22 (28.9 %) of 76 patients. All patients included in the study used bisphosphonate. The duration of taking bisphosphonate before fracture was 36.8 ± 50.8 (one–204 months) months. Fifty-seven (75 %) of 76 patients were taking the medication for more than three years. Delayed union occurred in 43 (56.5 %) of 76 patients. Delayed union was defined as a fractured bone that did not completely heal within six months of injury. The group of having taken anti-osteoporotic medication for more than three years showed relatively longer union period compared to that for a shorter period medication group (4.8 ± 2.5 months vs 9.3 ± 3.7 months, p = 0.017). The delayed union developed in 43 (56.5 %) of 76 patients and showed a significantly higher incidence in the group with long-term therapy (five/43 vs 38/43, p = 0.021). The bilateral femoral fractures developed in 23 (30.2 %) of 76 patients and showed a high incidence in the group medicated more than three years (two/23 vs 21/23, p = 0.039).

Conclusions

The longer bisphosphonates are used, the more the cases of delayed union and the more frequent the development of bilateral fractures following unilateral fractures. With regard to the delayed union, the methods of the acceleration of fracture healing may be beneficial in atypical femoral fracture patients who had been receiving long-term bisphosphonates therapy. Careful observation is required for contra-lateral femurs due to a high incidence of bilateral atypical femoral fractures.