What Is the Implant Survivorship and Functional Outcome After Total Humeral Replacement in Patients with Primary Bone Tumors?

BACKGROUND

Total humeral replacement is an option to reconstruct massive bone defects after resection of locally advanced bone tumors of the humerus. However, implant survivorship, potential risk factors for implant revision surgery, and functional results of total humeral replacement are poorly elucidated because of the rarity of the procedure.

QUESTIONS/PURPOSES

We asked: (1) What is the revision-free implant and overall limb survivorship after total humerus replacement? (2) What factors are associated with implant revision surgery? (3) What is the functional outcome of the procedure as determined by the Musculoskeletal Tumor Society (MSTS) score and the American Shoulder and Elbow Surgeons (ASES) score?

METHODS

Between August 1999 and December 2018, 666 patients underwent megaprosthetic reconstruction after resection of a primary malignant or locally aggressive/rarely metastasizing tumor of the long bones at our department. In all, 23% (154) of these patients had a primary tumor located in the humerus. During the study, we performed total humeral replacement in all patients with a locally advanced sarcoma, in patients with pathological fractures, in patients with skip metastases, or in patients with previous intralesional contaminating surgery, who would have no sufficient bone stock for a stable implant fixation for a single joint megaprosthetic replacement of the proximal or distal humerus. We performed no biological reconstructions or reconstructions with allograft-prosthetic composites. As a result, 5% (33 of 666) of patients underwent total humerus replacement. Six percent (2 of 33) of patients were excluded because they received a custom-made, three-dimensionally (3-D) printed hemiprosthesis, leaving 5% (31) of the initial 666 patients for inclusion in our retrospective analysis. Of these, 6% (2 of 31) had surgery more than 5 years ago, but they had not been seen in the last 5 years. Median (interquartile range) age at the time of surgery was 15 years (14 to 25 years), and indications for total humeral replacement were primary malignant bone tumors (n = 30) and a recurring, rarely metastasizing bone tumor (n = 1). All megaprosthetic reconstructions were performed with a single modular system. The implanted prostheses were silver-coated beginning in 2006, and beginning in 2010, a reverse proximal humerus component was used when appropriate. We analyzed endoprosthetic complications descriptively and assessed the functional outcome of all surviving patients who did not undergo secondary amputation using the 1993 MSTS score and the ASES score. The median (IQR) follow-up in all survivors was 75 months (50 to 122 months), with a minimum follow-up period of 25 months. We evaluated the following factors for possible association with implant revision surgery: age, BMI, reconstruction length, duration of surgery, extraarticular resection, pathological fracture, previous intralesional surgery, (neo-)adjuvant radio- and chemotherapy, and metastatic disease.

RESULTS

The revision-free implant survivorship at 1 year was 77% (95% confidence interval 58% to 89%) and 74% (95% CI 55% to 86%) at 5 years. The overall limb survivorship was 93% (95% CI 75% to 98%) after 1 and after 5 years. We found revision-free survivorship to be lower in patients with extraarticular shoulder resection compared with intraarticular resections (50% [95% CI 21% to 74%] versus 89% [95% CI 64% to 97%]) after 5 years (subhazard ratios for extraarticular resections 4.4 [95% CI 1.2 to 16.5]; p = 0.03). With the number of patients available for our analysis, we could not detect a difference in revision-free survivorship at 5 years between patients who underwent postoperative radiotherapy (40% [95% CI 5% to 75%]) and patients who did not (81% [95% CI 60% to 92%]; p = 0.09). The median (IQR) MSTS score in 9 of 13 surviving patients after a median follow-up of 75 months (51 to 148 months) was 87% (67% to 92%), and the median ASES score was 83 (63 to 89) of 100 points, with higher scores representing better function.

CONCLUSION

Total humeral replacement after resection of locally advanced bone tumors appears to be associated with a good functional outcome in patients who do not die of their tumors, which in our study was approximately one- third of those who were treated with a resection and total humerus prosthesis. However, the probability of early prosthetic revision surgery is high, especially in patients undergoing extraarticular resections, who should be counseled accordingly. Still, our results suggest that if the prosthesis survives the first year, further risk for revision appears to be low. Future studies should reexamine the effect of postoperative radiotherapy on implant survival in a larger cohort and evaluate whether the use of soft tissue coverage with plastic reconstructive surgery might decrease the risk of early revisions, especially in patients undergoing extraarticular resections.

LEVEL OF EVIDENCE

Level III, therapeutic study.

Type of bone graft and primary diagnosis were associated with nosocomial surgical site infection after high tibial osteotomy: analysis of a national database

PURPOSE

Although several small-scale studies have reported risk factors for surgical site infection (SSI) after high tibial osteotomy (HTO), no study has collectively analysed risk factors in a large cohort. The present study aimed to clarify the risk factors for SSI after HTO using a national database.

METHODS

Data of inpatients who underwent HTO from 2010 to 2017 were obtained from the Diagnosis Procedure Combination database in Japan. Outcome measures were the incidence of SSI and deep SSI after HTO. Associations between SSI and patient data were examined with multivariable logistic regression analysis.

RESULTS

Among 12,853 patients who underwent HTO, 195 developed SSI (1.52%) and 50 developed deep SSI (0.39%). Univariate analysis showed that male sex, smoking, and longer anaesthesia duration were associated with higher incidences of SSI, whereas a primary diagnosis of osteonecrosis and use of natural bone grafts were associated with lower incidences. In multivariable analysis, SSI was positively associated with male sex, anaesthesia duration longer than 210 min (vs. 150-210 min), and use of artificial bone graft (vs. natural bone graft). SSI was negatively associated with age ≤ 49 years (vs. 50-59 years) and a primary diagnosis of osteonecrosis (vs. osteoarthritis).

CONCLUSION

The present study revealed novel risk factors for SSI after HTO that previous studies have failed to find, including use of artificial bone graft and longer anaesthesia duration; primary diagnosis of osteonecrosis and younger age were novel protective factors. These findings will help surgeons assess risks of SSI after HTO in individual patients.

LEVEL OF EVIDENCE

III.

Femoral Periprosthetic Fracture Nonunion Management and Outcomes with Nonunion Repair and Retention of Primary Components

INTRODUCTION

Nonunion of a femoral periprosthetic fracture is a rare occurrence in orthopedic practice. Failure of a periprosthetic fracture to heal can lead to substantial disability and pain for patients as well as the potential need for component revision. Relatively little literature exists describing their management and outcome.

METHODS

Eleven patients with femoral periprosthetic fracture nonunion who presented for tertiary care were enrolled in a prospective data registry. Patients were considered to have developed nonunion following failure of progression in radiographic and clinical healing for a 6-month period. All patients were seen at standard postoperative intervals, and outcomes were recorded using the Short Musculoskeletal Function Assessment (SMFA), visual analog scale (VAS) for pain, physical examination, and radiographic examination. Preoperative radiographs were reviewed for classification.

RESULTS

Eleven patients had periprosthetic femoral fracture nonunion associated with prior hip (five patients) or knee (six patients) arthroplasty and were included in our study. Mean follow-up time was 30 months. Mean age at time of nonunion surgery was 64.5 years (range: 41.8 to 78.2 years). All patients underwent removal of previous fracture hardware at time of nonunion surgery. Ten (91%) of 11 received autogenous iliac crest bone grafting at time of nonunion surgery. Ten (91%) of the 11 patients went on to union without further intervention. Mean time to union was 7.9 months (SD: 8.0). The one patient that developed a persistent nonunion was complicated by infection requiring multiple irrigation and debridement procedures and total hip explant. The mean improvement in total SMFA score from baseline to final follow-up was 22.6 (p = 0.030). The greatest functional improvement was in the bothersome index at 28.0 (p = 0.028). The mean improvement in VAS pain score from baseline to final follow-up was 4.5 (p = 0.013).

DISCUSSION

Periprosthetic fracture nonunions can be successfully treated with operative intervention aimed at compression plating with bone graft and retention of primary components. In addition, successful periprosthetic nonunion repair improves function and pain in these patients.

Treatment of open intraarticular distal femur fractures by Ilizarov fixator; an approach to improve the outcome with mid-term results

PURPOSE

Open comminuted intraarticular distal femur fracture represents a formidable challenge for the orthopaedic surgeon for the inherent fracture complexity, soft tissue damage, and contamination. The purpose of this study was to evaluate the mid-term outcome results and safety of using the Ilizarov fixator to treat these fractures.

PATIENTS AND METHODS

The study included 22 fractures treated by debridement with reduction and stabilization by Ilizarov external fixator. The mean age was 35 years. Gustilo grade of open fracture was III-A (19 cases), III-B (2 cases), and III-C (1 case). Six fractures were AO-OTA type 33C2, and 16 cases were type 33C3. Eight patients had associated injuries. Bone and functional results were evaluated by Association for the Study and Application of the Method of Ilizarov (ASAMI) criteria, and Neer knee score. The statistical analysis was done using the IBM SPSS Statistics for Windows.

RESULTS

Seven cases had autogenous bone grafting. The frame crossed the knee in 8 patients. The fixator was removed after a mean of 7 months with union in all cases, and without any malalignment >5°. Deep infection occurred in two cases. Quadriceps-plasty was needed for 3 cases. After a mean of 44 months, the last follow-up results showed full knee extension and a mean flexion of 107.59°. The ASAMI functional and bone results were good to excellent in all cases. Neer knee score averaged 86.59.

CONCLUSIONS

Ilizarov fixator was an effective treatment modality of open comminuted distal femur fractures with high union rate, adequate alignment and satisfactory functional outcomes.

Comparison of curettage and bone grafting combined with elastic intramedullary nailing vs curettage and bone grafting in the treatment of long bone cysts in children

To compare the efficacy of curettage and bone grafting combined with elastic intramedullary nailing (EIN) vs curettage and bone grafting in the treatment of long bone cysts in children and to clarify the necessity of using EIN in the treatment of bone cysts.Sixty-two patients were involved in this study from Jan. 2009 to Sept. 2017 (43 males, 19 females; 27 humeri, 35 femurs); the patients were assigned to an EIN group, comprising 30 patients who underwent curettage and bone grafting combined with EIN, or to a non-elastic intramedullary nailing (NEIN) group, comprising 32 patients who underwent curettage and bone grafting alone. The prognosis of the 2 groups was assessed with reference to the standard of Capanna.No statistically significant differences in sex, age, location, activity, pathological fracture, cyst volume, operative time and intraoperative blood loss were found between the 2 groups (P > .05). The effective rate was 90.0% in the EIN group and 68.8% in the NEIN group, and the difference was statistically significant (P < .05).Compared to simple curettage and bone grafting, curettage and bone grafting combined with EIN treatment can significantly improve the prognosis of children with bone cysts. It is recommended that EIN be added to bone cyst curettage and bone grafting.

Fresh Osteochondral Allograft Transplantation for Treatment of Large Cartilage Defects of the Femoral Head: A Minimum Two-Year Follow-Up Study of Twenty-Two Patients

BACKGROUND

Controversy remains over the surgical management of large osteochondral lesions of the femoral head in young, active patients. The purpose of this study is to assess midterm clinical and radiographic outcomes after fresh osteochondral allograft transplantation (OAT) for large femoral head lesions at minimum 2-year follow-up.

METHODS

A retrospective review of prospectively collected data was performed for 22 patients under the age of 50 years with defined femoral head osteochondral lesions who underwent fresh OAT between 2008 and 2015. Patients were assessed clinically using the modified Harris Hip Score (mHHS) preoperatively and at each follow-up visit. Postoperative radiographs were evaluated for graft integrity and Kellgren & Lawrence Grade for osteoarthritis severity. Complications and reoperation were assessed by chart review. Kaplan-Meier survivorship analyses with 95% confidence intervals were performed for the end point of conversion to total hip arthroplasty.

RESULTS

At a mean follow-up of 68.8 months (26-113), the mean mHHS improved significantly (P < .001) from 48.9 (19-84) to 77.4 (35-98). Sixteen of 22 patients (72.7%) had an mHHS ≥70 at the latest follow-up. Arthritic progression, as indicated by an increase in the Kellgren & Lawrence Grade, occurred in 4 of 22 hips (18.2%). Five patients (22.7%) underwent conversion to total hip arthroplasty. Graft survivorship was 86.4 ± 7.3% at 2 years, 78.5 ± 10.0% at 5 years, and 67.3 ± 13.5% at 9 years.

CONCLUSION

Fresh OAT may be a viable treatment option for osteochondral defects of the femoral head in young, active patients with minimal preexisting joint deformity.

A UK-based pilot study of current surgical practice and implant preferences in lumbar fusion surgery

Lumbar fusion surgery is an established procedure for the treatment of low back pain. Despite the wide set of alternative fusion techniques and existing devices, uniform guidelines are not available yet and common surgical trends are scarcely investigated.The purpose of this UK-based study was to provide a descriptive portrait of current surgeons' practice and implant preferences in lumbar fusion surgery.A UK-based in-person survey was designed for this study and submitted to a group of consultant spinal surgeons (n = 32). Fifteeen queries were addressed based on different aspects of surgeons' practice: lumbar fusion techniques, implant preferences, and bone grafting procedures. Answers were analyzed by means of descriptive statistics.Thirty-two consultant spinal surgeons completed the survey. There was clear consistency on the relevance of a patient-centered management (82.3%), along with a considerable variability of practice on the preferred fusion approach. Fixation surgery was found to be largely adopted (96.0%) and favored over stand-alone cages. With regards to the materials, titanium cages were the most used (54.3%). The geometry of the implants influenced the choice of lumbar cages (81.3%). Specifically, parallel-shape cages were mostly avoided (89.2%) and hyperlordotic cages were preferred at the lower lumbar levels. However, there was no design for lumbar cages which was consistently favored. Autograft bone graft surgeries were the most common (60.0%). Amongst the synthetic options, hydroxyapatite-based bone graft substitutes (76.7%) in injectable paste form (80.8%) were preferred.Current lumbar fusion practice is variable and patient-oriented. Findings from this study highlight the need for large-scale investigative surveys and clinical studies aimed to set specific guidelines for certain pathologies or patient categories.

Utilization of ring-shaped bone allograft for surgical treatment of adolescent post-tubercular kyphosis: A retrospective study

This study aimed to investigate the mid-term outcome of ring-shaped bone allografts in the surgical treatment of adolescent post-tubercular kyphosis secondary to spinal tuberculosis.The records of adolescent patients diagnosed with spinal tuberculosis who received treatment in our department between 2009 and 2013 were retrospectively reviewed. The anterior approach was used in cases of cervical kyphosis and the posterior approach was used in cases of thoracic and lumbar kyphosis. During the surgery, the ring-shaped bone was used as a structural bone graft associated with the cancellous bone filing in the center portion of the ring shape. Cobb's angle, signs of spinal infusion on computed tomography, and complications were followed up.A total of 25 patients were included in our study. Among them, 3 involved the cervical region, 5 involved the thoracic region, 8 involved the thoracolumbar region, and 9 involved the lumbar region. The preoperative kyphosis deformity was a mean 65° Cobb's angle (40°-97°) compared to the postoperative 14° Cobb's angle (10°-21°) for an average correction of 51°. All wounds healed well without graft rejection. All patients achieved bone fusion 3 months postoperative for a 100% fusion rate.Our results show that the ring-shaped allograft bone is an effective option for the treatment of adolescent kyphosis. The ring-shaped allograft bone demonstrated satisfactory mechanical strength and vertebral fusion without mid-term metallic toxicity.

Survival of Dental Implants Placed in Grafted and Nongrafted Bone: A Retrospective Study in a University Setting

PURPOSE

To compare dental implant survival rates when placed in native bone and grafted sites. Additionally, risk factors associated with dental implant loss were identified. This study was based on the hypothesis that bone grafting has no effect on implant survival rates.

MATERIALS AND METHODS

A retrospective chart review was conducted for patients receiving dental implants at the University of Texas, School of Dentistry from 1985 to 2012. Exclusion criteria included patients with genetic diseases, radiation and chemotherapy, or an age less than 18 years. To avoid misclassification bias, implants were excluded if bone grafts were only done at the same time of placement. Data on age, sex, tobacco use, diabetes, osteoporosis, anatomical location of the implant, implant length and width, bone graft, and professional maintenance were collected for analysis.

RESULTS

A total of 1,222 patients with 2,729 implants were included. The cumulative survival rates at 5 and 10 years were 92% and 87% for implants placed in native bone and 90% and 79% for implants placed in grafted bone, respectively. The results from multivariate analysis (Cox regression) indicated no significant difference in survival between the two groups; having maintenance therapy after implant placement reduced the failure rate by 80% (P < .001), and using tobacco increased the failure rate by 2.6-fold (P = .001).

CONCLUSION

There was no difference in the dental implant survival rate when implants were placed in native bone or bone-grafted sites. Smoking and lack of professional maintenance were significantly related to increased implant loss.

A New Recommendation for Handling and Care of Human Allogenic Bone Graft (at Siriraj Hospital) to Reduce Post-Operative Complication

BACKGROUND

Bangkok Biomaterial Center is the only allogenic bone bank in Thailand, supplying the bones to all medical centers. From a report, a certain number of post-operative complications were found.

OBJECTIVE

To compare pre-protocol revision and post-protocol revision success rates and complications associated with the use of allogenic bone grafts relative to perioperative handling and care of allogenic bone.

MATERIAL AND METHOD

This retrospective comparative study was conducted at the Bangkok Biomaterial Center, Faculty of Medicine Siriraj Hospital, Mahidol University. All registration forms and surgical follow-up reports relating to the use allogenic bones procured from our bone bank between 2005 and 2015 were reviewed. New recommendations for the use of our allogenic bones were established in 2009. Results and complications after allogenic bone transplantation between 2005 and 2008 were compared with results and complications after transplantation to a new protocol between 2009 and 2015. Descriptive analysis and analysis of variance were used to evaluate the data.

RESULTS

Data of 825 patients who underwent deep frozen allogenic bone transplantation and 1,541 patients who underwent freeze-dried allogenic bone transplantation were retrospectively reviewed. Overall, the complication rate was reduced from 14.83% in the pre-protocol revision period to 5.15% in the period after the new recommendations for perioperative graft handling were established and implemented.

CONCLUSION

New recommendations for the handling and care of allogenic bone during the perioperative period significantly reduced post-operative complications in patients who received transplantation with deep frozen allogenic bone. The infection rate in patients who received allogenic bone graft was very low.

Structural allograft reconstruction of the foot and ankle after tumor resections

BACKGROUND

Structural allografts have been used to correct deformities or to fill bone defects secondary to tumor excisions, trauma, osteochondral lesions, or intercalary arthrodesis. However, the quality of published evidence supporting the use of allograft transplantation in foot and ankle surgery has been reported as fair. The purpose of this study was to report the overall survival of structural allograft in the foot and ankle after tumor resection, and the survival according to the type of allograft and the complication rates in the medium to long term.

MATERIALS AND METHODS

From January 1989 to June 2011, 44 structural allograft reconstructions of the foot and ankle were performed in 42 patients (28 men and 14 women) due to musculoskeletal tumor resections. Mean age at presentation was 27 years. Mean follow-up was 53 months. Demographic data, diagnosis, site of the neoplasm, operations performed, operative complications, outcomes after surgery, date of last follow-up evaluation, and local recurrences were reviewed for all patients. Regarding the type of 44 allograft reconstructions, 16 were hemicylindrical allografts (HA), 12 intercalary allografts (IA), 10 osteoarticular allografts (OA), and 6 were total calcaneal allograft (CA).

RESULTS

The overall allograft survival rate, as calculated with the Kaplan-Meier method, at 5 and 10 years was 79 % (95 % CI 64-93 %). When allocated by type of allograft reconstruction the specific allograft survival at 5 and 10 years was: 83 % for CA, 80 % for HA, 77 % for OA, and 75 % for IA. The complications rate for this series was 36 % including: articular failure, local recurrence, infection, fracture and nonunion.

CONCLUSION

This study showed that structural allograft reconstruction in the foot and ankle after tumor resection may be durable with a 79 % survival rate at 5 and 10 years. The two types of allografts that showed better survival rate were hemicylindrical allografts (80 %) and calcaneus allografts (83 %). The highest complication rates occurred after calcaneus allografts and osteoarticular allografts.

LEVEL OF EVIDENCE

IV.

[Sealing of Femoral Tunnel with Autologous Bone Graft Decreases Blood Loss]

PURPOSE OF THE STUDY Total knee arthroplasty is commonly used procedure with advanced stage arthritis which causes extensive blood loss intraoperatively and postoperatively. Purpose of this study is to show the effectiveness of sealing of femoral tunnel with bone grafting in preventing blood loss. MATERIAL AND METHODS 288 patients with primary bicompartmental knee arthroplasty who were operated in between April 2012 and June 2015 are retrospectively studied. Two groups are formed according to sealing of femoral tunnel with autologous bone graft or not. Group 1 was the plugged group with 192 patients and group 2 was the unplugged group with 96 patients. Operation time, arthrotomy method, anticoagulant therapy, postoperative care were similar in between two groups.'Independent sample t-test' is used to compare two groups as statistical method. RESULTS Postoperative lowest hemoglobin levels are higher in plugged group (p < 0.001). Drain outputs are much less than unplugged group (p < 0.001). There is no statistically significant difference between amount of given erythrocyte suspensions. DISCUSSION In the literature there are many attempts to reduce blood loss and allogenic blood transfusion. Some systemic or local usage of medical therapies, mechanical interventions such as cold application or intraoperative fibrin sealers are some of them. There are a few studies favoring usage of plugs and a few do not. Our findings showed less blood loss with usage of autologous bone grafting but did not significantly affect the blood transfusion amount. CONCLUSION Autologous bone grafting is a free to use, non-time consuming and an effective method to reduce blood loss. Key words: knee arthroplasty, plug, sealing of femoral tunnel, blood loss.

A Population-Based 16-Year Study on the Risk Factors of Surgical Site Infection in Patients after Bone Grafting: A Cross-Sectional Study in Taiwan

Bone grafting is a commonly used orthopedic surgical procedure that will provide bone formation in bone defects or regions of defective bone healing. A major complication following bone grafting is a postoperative recipient graft site infection that is associated with substantial mortality and increased use of medical resources. The purpose of the study was to identify the risk factors associated with infection after bone-grafting surgery.Data from 1,303,347 patients listed in the Taiwan National Health Insurance Research Database (NHIRD) and admitted to hospitals from 1997 through 2012 who underwent primary bone grafting (mean age: 46.57 years old; mean length of hospital stay: 8.04 days) were analyzed. The incidence of infection by age, hospital stay, gender, income, chronic disease (tuberculosis [TB]; diabetes mellitus [DM]; acquired immunodeficiency syndrome [AIDS]), fracture complications (nonunion; delayed union fracture), types of graft and hospital was evaluated.Three percent of the patients developed a postoperative recipient graft site infection. Multivariable analysis revealed that patients were more likely to develop a post bone-grafting surgery infection if they were older, had a longer hospital stay, were male, had a lower income, or had comorbid TB, DM, or AIDS. Patients were more likely to develop an infection if they had a nonunion, an alloplast graft, or treated in a local clinic.Our findings should provide a clinically relevant reference for surgeons who perform bone grafting. Patients should be informed of the potential risks.

Anterolateral radical debridement and interbody bone grafting combined with transpedicle fixation in the treatment of thoracolumbar spinal tuberculosis

This retrospective cohort study was conducted to evaluate the clinical outcomes of radical anterolateral debridement and autogenous ilium with rib or titanium cage interbody autografting with transpedicle fixation for the treatment of thoracolumbar tuberculosis. Spinal tuberculosis operation aims to remove the lesions and necrotic tissues, remove spinal cord compression, and reconstruct spinal stability. However, traditional operation methods cannot effectively correct cyrtosis or stabilize the spine. In addition, the patient needs to stay in bed for a long time and may have many complications. So far, the best surgical method and fixation method for spinal tuberculosis remain controversial. There were a total of 43 patients, 16 involving spinal cord injury, from January 2004 to January 2011. The patients were surgically treated for radical anterolateral debridement via posterolateral incision and autogenous ilium with rib or titanium cage interbody autografting and single-stage transpedicle fixation. All the patients were followed up to determine the stages of intervertebral bone fusion and the corrections of spinal kyphosis with the restoration of neurological deficit. The erythrocyte sedimentation rate (ESR) of these patients decreased to normal levels for a mean of 2.8 months. The function of feeling, motion, and sphincter in 16 paraplegia cases gradually recovered after 1 week to 3 months postoperatively, and the American Spinal Injury Association scores significantly increased at the final follow-up. Intervertebral bone fusions were all achieved postoperatively. No internal fixation devices were loose, extracted, or broken. There was no correction degree loss during the follow-up. The method of radical anterolateral debridement and autogenous ilium with rib or titanium cage interbody autografting and single-stage transpedicle fixation was effective for the treatment of thoracolumbar tuberculosis, correcting kyphotic deformity, and reconstructing spinal stability, obtaining successful intervertebral bony fusion and promoting the recovery of paraplegia. These results showed satisfactory clinical outcomes.

Controversies in Cervical Discectomy and Fusion: Practice Patterns Among Canadian Surgeons

Objective:

Optimal fusion technique and peri-operative management of patients undergoing anterior cervical discectomy (ACD) is unclear.We document current practice patterns among Canadian spinal surgeons regarding the surgical management of single level degenerative cervical spondylosis.

Methods:

We conducted a web-based survey of neurosurgeons and spinal orthopedic surgeons in Canada. We asked questions pertaining to the management of single level cervical degenerative disc disease causing radiculopathy and/or myelopathy, including frequency of fusion following single-level discectomy, preferred fusion technique, indications and frequency of use of anterior plating, and use of an external cervical orthosis following surgery. Demographic factors assessed included training background, type and length of practice.

Results:

Sixty respondents indicated that their practice involved at least 5% spine surgery and were included in further analysis. Neurosurgeons comprised 59% of respondents, and orthopedic surgeons 41%. Fusion was employed 93% of the time following ACD; autologous bone was the preferred fusion material, used in 76% of cases. Neurosurgeons employed anterior cervical plates in 42% of anterior cervical discectomy and fusion cases, whereas orthopedic surgeons used them 70% of the time. External cervical orthoses were recommended for 92% of patients without plates and 61% of patients with plates. Surgeons who had been in practice for less than five years were most likely to be performing spinal surgery, using anterior cervical plates, and recommending the postoperative use of cervical orthoses.

Conclusion:

Practice patterns vary among Canadian surgeons, although nearly all employ fusion and many use instrumentation for single-level ACD. Training background, and type and length of practice influence practice habits.

[Medial proximal tibia donor site: contribution to alveolar cleft repair in children]

INTRODUCTION

Cancellous bone is the best material for alveolar cleft repair (or secondary alveolar cleft repair). It is usually harvested from the iliac bone but morbidity of this donor site is high. Among the other possible donor sites the tibial harvesting procedure seems safe with lower morbidity. The authors assessed the medio-proximal tibial harvesting procedure on a consecutive series of 55 children having undergone secondary alveoloplasty.

PATIENTS AND METHOD

An individual questionnaire was used to assess retrospectively the intensity and duration of postoperative pain, functional impotence, possible late complications, and scar length. Postoperative tibial in frontal and profile radiographs were used to assess corticotomy diameter, the distance between corticotomy and growth plate, and local complications.

RESULTS

The mean patient age was nine years. No complications were reported. Sixty nine percent of patients complained of postoperative pain with an average intensity of four out of 10 for a period of 17 days. Sixty five percent of patients complained of discomfort in walking for an average of 12 days. The average scar length was 10 mm. Two patients (3.6%) presented with sequels two years after surgery, residual scar pain for one, and painless ectopic tibial ossification next to the sampling site for the other.

DISCUSSION

The medio-proximal tibial site bone harvesting morbidity is low. The surgical procedure is easy, rapid, and safe. The amount of cancellous bone collected is sufficient for two simultaneous alveolar defect grafts. This site seems especially well adapted for secondary alveoloplasty in children.

An inventory of mandibular fractures associated with implants in atrophic edentulous mandibles: a survey of Dutch oral and maxillofacial surgeons

PURPOSE

The present study provides an inventory of the number of fractures that occurred in conjunction with implant placement in edentulous patients in the Dutch population from 1980 to 2007 and estimates the incidence with which this might occur. The study also sought to define the factors that increase the risk of fracture.

MATERIALS AND METHODS

Questionnaires were sent to all 198 oral and maxillofacial surgeons working in 56 hospitals in the Netherlands. Questions were asked regarding the causes of fractures, the height of the edentulous mandible, and the methods of fracture treatment.

RESULTS

Responses were received from 53 of the 56 departments. During the study period, 157 edentulous mandibles fractured in conjunction with implant treatment. All fractures occurred in mandibles with less than 10 mm of height, as measured in the symphysis. An incidence of less than 0.05% was estimated based on an estimated number of 475,000 patients treated with at least two implants during this time to support an overdenture. Reasons for early implant failures were insufficient bone volume, iatrogenic causes, nonintegration, and a narrow arch. Peri-implantitis, trauma, and explantation were associated with fractures occurring 1 year or more after implant placement. Several methods were employed to treat the fractured mandibles, including closed reduction, rigid fixation using osteosynthesis plates, and bone grafts with fixation. In 52% of patients, fracture healing was uneventful; however, in 48% of patients, complications were encountered, including osteomyelitis, nonunion, plate fracture, screw loosening, and dehiscences with subsequent infections.

CONCLUSIONS

Mandibles with a height of 10 mm or less, as measured at the symphysis, are at risk of fractures and associated complications. The provision of proper informed consent regarding the advantages and disadvantages of placing implants in thin mandibles is essential.

Bone banking in a community hospital

Major orthopaedic operations are now also performed in community hospitals. Because allografts are sometimes used during these procedures, local bone banking could become an essential tool. We evaluated the indications and results of the allografts from the local bone bank used in our institution. The financial aspect was also examined. Of the 131 allografts stored in our bone bank, only 20 were discarded. Postoperative follow-up showed good ingrowth of the grafts except for one graft failure. There were no superficial or deep postoperative infections. All cultures taken during implantation remained negative. These data suggest that bone banking in a community hospital is a safe and practical alternative to address the ongoing demand of bone grafts in a small orthopaedic practice. Financial costs are reasonable. In our experience, bone banking also broadens the spectrum of orthopaedic operations that can be performed in an orthopaedic unit.

[Acetabular reconstruction in revision arthroplasty. Retrospective study of 76 cases. Hospital Español de México]

OBJECTIVE

To review our experience with the various acetabular reconstruction techniques used during revision arthroplasty based on the defect in each patient.

MATERIAL AND METHODS

We undertook a retrospective, descriptive, observational study of patients who underwent acetabular reconstruction during revision ar. throplasty, from January 1997 to January 2005. We documented the type of acetabular defect, the type of cup and graft used, the complications, and the pre- and postoperative assessment with the Harris scale. Data were analyzed with the SPSS software and the Wilcoxon test (p < 0.05).

RESULTS

Seventy-six patients underwent surgery. Mean time elapsed between the primary replacement and the revision was 5 years. The acetabular defects found were: 16 type I, 22 type II, 30 type IIIA, and 8 type IIIB. The mean Harris score was 44 preoperatively and 76 postoperatively. The most frequently used technique involved the use of an autograft, a structural allograft with a porous threaded cup or a reinforcement ring. The most common complications included dislocation 5%, infection 3%, graft loss and cup loosening 21%, and loss of the hip center of rotation 15% (p < 0.05).

CONCLUSIONS

Acetabular reconstruction is technically challenging and involves high failure and complication rates, thus providing little improvement in patient activity. It is important to restore the hip center of rotation to improve function. The reconstruction techniques we used are the most common ones and are described in the literature.

The efficacy of rhBMP-2 for posterolateral lumbar fusion in smokers

STUDY DESIGN

Retrospective review of prospectively collected data, as part of an IRB-approved, FDA-regulated, randomized, nonblinded IDE trial of rhBMP-2 matrix for lumbar spinal fusion.

OBJECTIVES

The purpose of this study is to examine the influence of smoking on fusion rate and outcome in a large series of patients treated with an rhBMP-2 matrix (AMPLIFY) or iliac crest bone graft as part of a randomized IDE trial for single-level lumbar fusion.

SUMMARY OF BACKGROUND DATA

Preclinical studies suggest that bone morphogenetic proteins (BMPs) are able to reverse the negative influence of nicotine on fusion healing in animal models. It remains unclear if a similar benefit will be seen in humans, and if so, what formulation and amount of BMP will be required to achieve that improvement.

METHODS

We reviewed the clinical and radiographic records of 148 patients who underwent single-level instrumented lumbar fusion at three spine centers as part of an ongoing FDA-regulated IDE trial. Clinical outcome measures included Oswestry Disability Index, SF-36, back, and leg pain scores. Radiographic measures were plain radiographs with flexion-extension views and fine cut computed tomography scans with sagittal and coronal reconstruction. Fusion success was determined by independent radiologist readings.

RESULTS

At 2 years postoperatively, solid fusion was demonstrated in all 55 nonsmokers in the rhBMP-2 group (100%). Successful fusion was seen in 20 of 21 smokers in the rhBMP-2 group (95.2%). Fusion was achieved in 48 of 51 nonsmokers in the iliac crest bone graft (ICBG) group (94.1%), but only 16 of 21 smokers (76.2%) in the ICBG group.

CONCLUSIONS

The results of this study suggest that rhBMP-2 may enhance fusion rate in cigarette smokers undergoing single-level instrumented posterolateral lumbar fusion. Despite the improvement in fusion rate with rhBMP-2, clinical outcomes measures were still adversely affected in smokers.

Immediate Reconstruction of Mandibular Defects: A Retrospective Report of 242 Cases

PURPOSE

This study was conducted to evaluate the effects of routine protocols in immediate mandibular reconstruction.

PATIENTS AND METHODS

A total of 242 patients who underwent immediate mandibular reconstruction were reviewed retrospectively. The therapeutic evaluation was performed according to outcomes of clinical and radiographic examination. The evaluated contents included facial symmetry, degree of mouth opening, occlusal relationship, and temporomandibular joint symptoms. Statistical analysis was also carried out to compare therapeutic differences between different methods for mandibular reconstruction. SPSS 10.0 for Windows was used for statistical analysis.

RESULTS

The follow-up showed satisfactory long-term outcome in 203 patients. Statistical analysis revealed no significant difference in restoration of facial contour among several groups (chi(2) 0.05(15) = 21.93; P = .109 > .05). Ten cases involved serious postoperative complications, including local infection, exposure of rigid fixation plate, and serious pain.

CONCLUSIONS

Our findings indicate that autogenous bone graft is the best for reconstruction of small mandibular defects. Frozen autogenous lesional mandible plus autogenous iliac or rib graft is recommended for reconstruction of large defects in the mandible. Strict patient selection, careful surgical procedure, and appropriate preoperative and postoperative nursing care are key factors in successful transplantation.

Evaluation of bone availability in the cleft area following secondary osteoplasty

INTRODUCTION

Osteoplasty in cleft patients provides a basis for shaping a closed dental arch. This study aimed at a radiological appraisal of transplantation success following secondary osteoplasty by means of alveolar bone height as related to some selected influencing factors.

MATERIAL AND METHODS

In this study, postoperative radiographs of 46 patients with unilateral or bilateral clefts of lip, alveolus and palate were analyzed retrospectively. Alveolar bone height was typed according to Abyholm and Bergland and evaluated in consideration of dentition at the time of surgery and existence of the lateral incisor.

RESULTS

In total, 76% (n = 35) successes (type I/II) were observed. 6 out of 46 patients (13%) had to be re-operated for osteoplasty at a later date. A non-significantly higher rate of successes occurred during the early mixed dentition. In patients with existing lateral incisor, a higher rate (78% vs. 68%) of alveolar bone heights type I/II was obtained.

CONCLUSION

The successful surgical outcome in terms of alveolar bone height is facilitated by treatment onset preferably during early mixed dentition and in presence of the lateral incisor. Although maximal success rates cannot be obtained using this method, the utility and effectiveness of secondary osteoplasty in cleft patients has been confirmed.

Kyphosis One Level Above the Cervical Disc Disease

If present, kyphotic angulation is generally at the level of the cervical disc disease (CDD) in the neck, but sometimes occurs at one level above the CDD. We name this situation as kyphosis one level above (KOLA). KOLA CDD has not been studied previously. In this study, we present 18 patients who had KOLA among 147 patients operated for CDD over a 5-year period. Seven of these 18 patients also received surgery for their KOLA. As new, surgical treatment of kyphotic level was performed with plating and without bony fusion in 5 patients. Clinical outcomes (according to Odom's criteria) and kyphotic corrections of KOLA patients receiving and not receiving surgery for their kyphosis during were compared. The 7 KOLA patients having surgery to correct the kyphosis had a mean 20.14+/-3.13 degrees correction in their kyphosis (from mean 12.85 to -7.28 degrees), whereas the 11 patients undergoing surgery only for CDD showed only a mean 3.00+/-2.52 degrees correction (from mean 7.45 to 4.45 degrees). When kyphotic corrections were compared, statistically significant difference was found between 2 groups (P<0.01). Clinical outcome scores showed a trend towards improvement in the patients operated upon for kyphosis correction. KOLA may be a factor in the development of cervical disc herniation and spondylosis, and should be treated if more than 11 degrees. In cervical region, upper adjacent level disease may be an extension of KOLA. Larger studies can further define the relationship between KOLA and CDD, and indications for surgical correction of KOLA.

Are bone autografts still necessary in 2006? A three-year retrospective study of bone grafting

Autograft is considered as the gold standard in bone grafting. However, the development of tissue banks has allowed for a wider use of bone allografts, with good results. Demineralised Bone Matrix (DBM) and recombinant human Bone Morphogenetic Proteins (rh-BMP's) were also introduced to replace the time-honoured autograft. Is there currently still a place for bone autograft? The authors reviewed the orthopaedic surgical activity in their institution during the period 2003-2005, and traced all the surgical procedures in which bone grafting was performed. Tracking forms from the tissue bank were reviewed to assess the surgical indications. Between 2003 and 2005, the use of autografts decreased from 1.3% to 0.9% of all surgical interventions, particularly owing to their decreased use in primary fusions, while the use of allografts increased from 10.7% to 12.7%. Indications for allografts covered all fields of orthopaedic surgery, including nonunions. Processed allografts represented 90% of all grafts used. DBM and rh-BMP were used on an exceptional basis. There is currently a trend for surgeons to use allografts as substitutes for autografts, as processing of the allografts increases their safety while preserving most of their biological and mechanical properties. Autografting is now limited to revision operations after failed fusions, and to combined use at the junction with massive allografts. DBM and rh-BMP are still controversial but they might replace autografts, even in their currently remaining indications, if their cost effectiveness and efficiency are established.

The use of human tissue in bone grafting techniques

The Medicines and Healthcare products Regulatory Agency has informed hospitals in England and Wales that bone graft material, which may include bone obtained illegally without consent, may have been implanted into a small number of UK patients. This article outlines the technique of bone grafting, examines the normal regulation and safety considerations and highlights the nursing implications surrounding this issue.

The influence of cranioplasty on postural blood flow regulation, cerebrovascular reserve capacity, and cerebral glucose metabolism

The indications for cranioplasty after decompressive craniectomy are cosmetic repair and, mainly, restoration of cerebral protection. Although neurological improvement after cranioplasty is repeatedly noted, the reasons for this still remain unclear. Few observations concerning the impact of CSF hydrodynamic and/or atmospheric pressure were published during the last decades. Relevant data concerning the cerebrovascular reserve capacity and cerebral glucose metabolism before and after cranioplasty have been lacking until now. To gain further insight, the present study was undertaken to investigate the impact of cranioplasty on indices of cerebral blood flow regulation and metabolism. Thirteen patients in whom extensive craniectomies had been performed underwent a meticulous study of blood flow velocities in the middle cerebral artery (MCA) and extracranial internal carotid artery (ICA), as assessed by transcranial Doppler (TCD) ultrasonography during postural maneuvers (supine and sitting positions) and during stimulation with 1 g of acetazolamide for the interpretation of cerebrovascular reserve (CVR) capacity. Twelve patients underwent 18-fluorodesoxyglucose positron emission tomography. These measurements were made before and 7 days after cranioplasty. Cranioplasty improved preoperative differences in MCA blood flow velocities when comparing the injured with the noninjured hemisphere. Similarly, cranioplasty resolved decreases in extracranial ICA blood flow in the injured hemisphere that were induced by postural changes, which was a constant finding prior to this procedure. More strikingly, however, the CVR capacity, which was severely impaired in both hemispheres, significantly increased after the procedure. Metabolic deficits, which were observed in the injured as compared with the noninjured hemisphere, were found to improve after reimplantation of the skull bone flap. Cranioplasty appears to affect postural blood flow regulation, CVR capacity, and cerebral glucose metabolism markedly. Thus, early cranioplasty is warranted to facilitate rehabilitation in patients after decompressive craniectomy.

Tissue banking in Mexico

INTRODUCTION

Here, we describe our Tissue Banking experiences of 4 years of activity in Mexico.

METHODS

Data of allografts provided by our Bank and bone retrievals performed by our teams between February of 2001 and August of 2004 were included.

RESULTS

There were 100 bone donors, a total of 1,107 tissues were obtained with an average of 11 tissues by retrieval, samples from all tissues were obtained during retrieval and cultured for bacterial contamination, 250 tissues were positives to bacterial growth with an average of 22.58% of bacterial contamination of tissue by retrieval. A total of 4,493 allografts were provided and were utilized in 3,643 patients. The allografts were used mainly by orthopedic surgeons (62%) and dentists (30%). The most used allografts were morcellized cancellous bone 31%, pulverized 25% and chips of cancellous bone 20%. Among orthopedic patients the most frequent procedures were related with spine degenerative diseases 39.09%, followed by non-pathological fractures and its complications 28.67% and bone tumors and cystic bone lesions 11.59%.

CONCLUSIONS

Sustained increase of allograft utilization in Mexico reflects a great necessity for them in our country. The increase in public awareness about tissue donation has allowed an increase in tissue donations and retrievals.

Is retrieval of bone material from multiorgan donors effective enough to cover demand for biostatic bone tissue grafts in Poland?

In Poland there is growing demand for biostatic allogeneic bone transplantation mostly for traumatologic operations and orthopedic reconstructions. The bone material is primarily harvested during postmortem examinations in forensic and pathology laboratories. Nevertheless, the collected amounts are not sufficient, so that material needs to be acquired from alternative sources, such as multiorgan donors. Between 1998 and 2003, 2331 potential donors were registered by the Transplantation Coordinating Center in Warsaw, which was adjusted to 1794 donors who would have been accepted as donors of the bone tissue. Unfortunately, due to denials from family members and public prosecutors, the sample was only 1416 donors, which would cover about 40% of the clinical orthopedic demand in Poland.

Cage containing a biphasic calcium phosphate ceramic (Triosite) for the treatment of cervical spondylosis

BACKGROUND

We evaluated the fusion efficacy and clinical outcomes of a cage containing a biphasic calcium phosphate ceramic (Triosite) in treating cervical spondylosis.

METHODS

We randomly divided 100 patients with cervical spondylosis undergoing anterior discectomy with interbody polyetheretherketone (PEEK) fusion into 2 groups in the past 2 years: group A (n = 50), PEEK cage containing a biphasic calcium phosphate ceramic (Triosite), and group B (n = 50), PEEK cage containing an autogenous iliac bone graft. We compared the fusion rate, fusion time, spinal curvature, and neuroforamen size between the 2 groups. We also compared excess operation time, excess blood loss, hospital stay, complications, and neurological recovery status between the groups.

RESULTS

The fusion rates were 57%, 67%, 77%, 82%, 92%, and 100% in group A and 81%, 86%, 95%, 95% 100%, and 100% in group B in the first 6 postoperative months. The fusion rate in group A was significantly lower than that in group B in the first 5 months after the procedure (P < .05 and P < .01, respectively), but the fusion rate reached 100% in both groups by the sixth month. Within the first 6 months, as the fusion level increased, the fusion rates reduced and time to fusion was delayed in both groups. There were no donor site complications in group A. However, 3 patients (6%) from group B experienced complications (1, wound infection; 1, numbness of thigh; and 1, subcutaneous hematoma) (P < .001). The hospital stay was shorter in group A (4.43 +/- 2.36 days) than in group B (7.00 +/- 3.77 days) (P = .001). The mean excessive blood loss and excessive operative time for an iliac bone graft in group B were 15 +/- 5 mL and 10 +/- 6 minutes. There was no statistical significance in spinal curve correction, neuroforamen enlargement, and neurological recovery.

CONCLUSIONS

A cage containing a biphasic calcium phosphate ceramic resulted in complete fusion by the sixth postoperative month, although the fusion rate was lower than that in a cage containing an autograft during the first 5 months after the operation and the time to fusion was delayed. Using a cage containing a biphasic calcium phosphate ceramic leads to a shorter hospital stay, less blood loss, shorter operative time, and no donor site complications. It seemed to be a good substitute for cervical spondylotic fusion.

Allograft bone in spinal fusion for adolescent idiopathic scoliosis

OBJECTIVE

The purpose of this long-term study was to determine the efficacy of allograft bone for spinal fusion for adolescent idiopathic scoliosis. Prior studies comparing allograft and autograft have been short term.

METHODS

This multicenter retrospective study was carried out on 111 patients with 132 total curves fused for adolescent idiopathic scoliosis. Minimum follow-up was 5 years (average 72 months). A variety of segmental instrumentation was used, with most being dual-rod, multiple-hook constructs.

RESULTS

Average preoperative curve was 59 degrees with immediate correction to 29 degrees (51%) and final follow-up of 32.24 degrees (45.4%). Average loss of correction was 3.5 degrees (5.9%). There were three pseudarthroses, one infection, and no rod breakage.

CONCLUSION

Pseudarthrosis rate of 2.7% and loss of correction of 5.9% are comparable with or better than those in previous reports using autogenous bone graft and either segmental or nonsegmental instrumentation.

Infection in massive bone allografts

We studied a series of 945 patients who received cadaveric allografts implanted for nonpelvic bone or soft tissue tumor lesions since 1971. We specifically were interested in the role of infection in the graft process, and, more specifically its history, frequency, and affect on outcome. Primary infections (not related to reoperations for nonunions or fractures of the graft) occurred in 75 patients (7.9%), and an additional 46 patients had infections related to reoperations, increasing the total number of patients with infections to 121 (12.8%). The highest frequency of infection occurred in patients with soft tissue tumors, radiated sites, Musculoskeletal Tumor Society Stage IIB tumors, or surgeries consisting of an allograft arthrodesis. Most of the infected grafts failed; however, none of the patients died. One patient had hepatitis C develop, and one patient became HIV positive after receiving the virus from a blood transfusion. A comparison with other series of surgically treated patients, including those receiving metallic devices, suggests that the infection rate may be related to the surgery or the graft's immunologic resistance, rather than the graft. The problem of infection is a major issue for tumor surgeons. Suggestions regarding how to decrease the frequency of this complication are presented.

Persistent swallowing and voice problems after anterior cervical discectomy and fusion with allograft and plating: a 5- to 11-year follow-up study

Anterior cervical discectomy and fusion is commonly performed for cervical disc disease. Most studies report that swallowing and voice problems after such surgeries tend to resolve with time and are often of minor significance except in the rare cases of recurrent laryngeal nerve palsies. A retrospective review was performed on patients who had anterior cervical discectomy and fusion by a single surgeon more than 5 years prior, to determine the persistence of swallowing and voice problems in them. Seventy-four patients who had anterior cervical discectomy and fusion with allograft and plating an average of 7.2 years prior responded to an invitation to return for a follow-up clinical review. Emphasis was placed on the symptoms of dysphagia and dysphonia, as related to the index surgery. At final review, persistent dysphagia was present in 26 patients (35.1%). This occurred more frequently in females and in younger patients. Dysphonia at final review persisted in 14 patients (18.9%). This also occurred more commonly in females and in patients in whom possible non-union is present in at least one of the levels operated upon. Problems with singing were present in 16 patients (21.6%) postoperatively, occurring more frequently if the C3/4 disc was included in the surgery and in patients who have had a greater total number of anterior cervical surgeries at the time of review. Dysphonia and dysphagia are persistent problems in a significant proportion of patients, even beyond 5 years after anterior cervical spine surgery.

Failure of reconstitution of open-section, posterior iliac-wing bone graft donor sites after lumbar spinal fusion. Observations with implications for the etiology of donor site pain

The objective of this cohort study--conducted at a regional trauma unit in southern Ontario, Canada--was to review the imaging history of open-section, iliac-wing bone graft donor sites in lumbar fusion patients. Intervention entailed review of available X-ray and CT scan images for all patients undergoing lumbar fusion with iliac autograft in the senior author's practice over a 4-year period. Outcome was radiographic confirmation of the absence of bony reconstitution at the iliac harvest site. Of 239 primary fusions performed, 209 complete imaging records were available for review. The images of a further 20 patients who had surgery with the senior author prior to the study period and who presented at the office in the first half of 2000 were also assessed. All cases showed persistence of the iliac donor harvest site defect. Only minimal marginal sclerosis to suggest attempted remodeling was observed. We conclude that iliac-wing bone graft donor sites do not remodel. Given that iliac harvesting is known to increase strain in the pelvis, and that lumbosacral stabilization increases stress in the pelvis, permanent deficiency of iliac bone stock at donor harvest site may be a factor in both primary donor site pain and the observed high frequency of this problem in lumbosacral fusion patients.

Predictors of outcomes after posterior decompression and fusion in degenerative spondylolisthesis

No consensus has been reached regarding surgical management of degenerative spondylolisthesis. The optimal type of surgical procedure and surgical indications have not been precisely defined. In order to screen for predictors of outcome, we retrospectively studied patient outcomes after posterior decompression and fusion for isolated lumbar degenerative spondylolisthesis. Twenty-four consecutive patients (age range 50-78 years) underwent primary surgery for isolated lumbar degenerative spondylolisthesis. The surgical procedure consisted of posterior decompression and pedicle screw instrumented fusion using autogeneous bone graft, with or without interbody fusion. Clinical and radiologic status were assessed using the Beaujon functional score and plain AP and lateral radiographs. A multivariate analysis was used to correlate the functional score increase with surgical procedure modifications and preoperative clinical and radiologic features in order to determine which of them led to better results. Eighteen patients completed the evaluation. Six others were lost to follow-up after a minimum of 0.87 years. Combining all the results, the mean follow-up was 2.87 years. The Beaujon score was improved in the 24 patients (P<0.001), and fusion was successful in all cases. Additional interbody fusion and preoperative leg pain were significantly correlated with larger score increase (P=0.016 and P=0.003). Posterior decompression and fusion is successful in treating lumbar degenerative spondylolisthesis. From this study, circumferential fusion improves the outcomes and leg pain is a fair indication for surgery.

Comparison of implant survival following sinus floor augmentation procedures with implants placed in pristine posterior maxillary bone: a systematic review

Sinus augmentation is a commonly used procedure in implant dentistry. However, a general consensus on implant survival after this procedure is still lacking. The objective of this study was to systematically review implant survival following sinus augmentation procedures compared with conventional implant placement in the posterior maxilla. Following the production of a detailed protocol, screening and quality assessments of clinical trials were conducted in duplicate and independently. The search yielded 579 abstracts and 93 were selected for full-text screening. Six publications (five studies) fulfilled all the inclusion criteria and were relevant to the study. Heterogeneity of the selected papers prevented meta-analysis. Implant survival ranged from 73% to 100% for non-augmented sinuses and from 36% to 100% for augmented sinuses in patient-based data. From implant-based data, survival varied between 75% and 100% for both non-augmented and augmented areas. Implant survival appears to show greater variability in grafted sinuses than in the posterior maxilla. However, prospective studies with larger patient numbers and control of confounding factors are urgently needed to provide definitive data on this important procedure.

A retrospective review of cervical corpectomy: indications, complications and outcome

BACKGROUND

Cervical corpectomy is a common spinal surgery procedure used to decompress the spinal cord in numerous degenerative, traumatic and neoplastic conditions. The aim of this study was to investigate the indications, complications and outcomes in past cervical corpectomy cases at one centre.

METHOD

72 patients who underwent cervical corpectomy between February 1992 and June 2001 were retrospectively investigated.

FINDINGS

The indications for this operation were degenerative spondylitic disease (26 cases; 36.1%), trauma (18 cases; 25%), tumour (11 cases; 15.3%), infection (10 cases; 13.9%), and ossification of the posterior longitudinal ligament (7 cases; 9.7%). Thirty-seven patients (51.4%) underwent one-level corpectomy, and 35 (48.6%) underwent two-level corpectomy. Autografts were used in 13 cases (18.1%) and allografts were used in 59 cases (81.9%). Anterior plate-screw fixation was performed in all cases. There were 31 postoperative complications in 15 (20.8%) patients. Twelve of the complications were surgical, 5 were graft-related, 7 were plating-related, and 7 were medical. Solid bony fusion was achieved in 65 (92.9%) of the 70 surviving patients. The mean follow-up time was 23.4 months. An overall favourable outcome was achieved in 88% of cases.

CONCLUSION

The outcomes in this series indicate that cervical corpectomy is an effective method for treating traumatic lesions, degenerative disease, tumours and infectious processes involving the anterior and middle portions of the cervical spine.

Bone and tissue allograft use by orthopaedic surgeons

The purpose of our study was to determine the involvement of orthopaedic surgeons in the process of acquiring allografts they transplant. A questionnaire regarding allograft acquisition and use was directed to 340 hospitals. In approximately 85% of the institutions, nonorthopaedic personnel selected and acquired the allografts. In most, those responsible for providing surgeons with allografts had little or no knowledge of the practices of tissue banking and allograft transplantation biology. In about 15% of the hospitals, the surgeon was involved in the selection of the source of allografts. It is imperative that orthopaedic surgeons who transplant bone and tissue allografts become actively involved in determining the source and processing of tissue transplants they place in their patients.

Comparative study of laparoscopic L5-S1 fusion versus open mini-ALIF, with a minimum 2-year follow-up

Anterior lumbar interbody fusion (ALIF) is a widely accepted tool for management of painful degenerative disc disease. Recently, the modern laparoscopic surgical technique has been combined with ALIF procedure, with good early postoperative results being reported. However, the benefit of laparoscopic fusion is poorly defined compared with its open counterpart. This study aimed to compare perioperative parameters and minimum 2-year follow-up outcome for laparoscopic and open anterior surgical approach for L5-S1 fusion. The data of 54 consecutive patients who underwent anterior lumbar interbody fusion (ALIF) of L5-S1 from 1997 to 1999 were collected prospectively. More than 2-years' follow-up data were available for 47 of these patients. In all cases, carbon cage and autologous bone graft were used for fusion. Twenty-five patients underwent a laparoscopic procedure and 22 an open mini-ALIF. Three laparoscopic procedures were converted to open ones. For perioperative parameters only, the operative time was statistically different (P=0.001), while length of postoperative hospital stay and blood loss were not. The incidence of operative complications was three in the laparoscopic group and two in the open mini-ALIF group. After a follow-up period of at least 2 years, the two groups showed no statistical difference in pain, measured by visual analog scale, in the Oswestry Disability Index or in the Patient Satisfaction Index. The fusion rate was 91% in both groups. The laparoscopic ALIF for L5-S1 showed similar clinical and radiological outcome when compared with open mini-ALIF, but significant advantages were not identified, despite its technical difficulty.

Reduction of disc space distraction after anterior lumbar interbody fusion with autologous iliac crest graft

STUDY DESIGN

A retrospective review with long-term clinical and radiologic assessment was conducted.

OBJECTIVE

To assess the severity and reasons for the reduction of disc space distraction after successful autograft fusion of the lumbar spine and its clinical consequences.

SUMMARY OF BACKGROUND DATA

Anterior lumbar interbody fusion is an established treatment for lumbar disc degeneration. It is not firmly established whether the grafted level narrows after surgery, and if so, what the clinical consequences are.

METHODS

This study assessed 67 patients who underwent anterior lumbar interbody fusion at L4-L5 with autologous iliac crest graft. The disc space height and angle between L4 and L5 were serially measured. Times until fusion and the presence of symptoms before and after surgery and at the latest follow-up assessment were noted.

RESULTS

The mean follow-up period was 14 years (range, 2.5-32 years). The fusion rate was 96% (64 of 67 patients), and the mean time to fusion was 9 months. In the group that had successful fusion, there was an initial increase in disc space distraction followed by a reduction in 55 patients (86%). The mean preoperative disc space height was 12.1 mm, which increased immediately after surgery to 16.2 mm, but had been reduced to 12.6 mm at the latest follow-up assessment. The reduction in distraction occurred within the first 3 months after surgery and was correlated with age, but not with recurrence of symptoms, the amount of initial distraction, or the gender of the individual. A similar trend was seen with L4-L5 segmental angulation.

CONCLUSIONS

Reduction of disc space distraction after anterior lumbar interbody fusion using tricortical iliac crest bone graft is a common finding. Despite this, the fusion rate is high, and there is no association with symptom recurrence.

National and regional rates and variation of cervical discectomy with and without anterior fusion, 1990-1999

STUDY DESIGN

A national hospitalization database was used to determine rates and trends in the treatment of cervical disc disease.

OBJECTIVE

To examine the temporal and geographic variations in hospitalizations and surgical procedures for cervical disc disease.

SUMMARY OF BACKGROUND DATA

Studies of spinal surgery during the 1980s showed significant increases in the rates for all procedures, particularly those involving fusion. The management of cervical disc disease continues to be controversial.

METHODS

Data from the National Hospital Discharge Survey from 1990 through 1999 were analyzed. Records were selected and categorized according to an algorithm of International Classification of Diseases (ICD-9) procedure and diagnosis codes.

RESULTS

During the study period, the rate of hospitalization for surgical and nonsurgical treatment of cervical disc disease did not increase significantly. There was, however, a statistically significant increase in the proportion of hospitalizations for the surgical treatment of cervical disc disease that included a fusion procedure. There also was significant geographic variation in the rate of fusion procedures, with the South having the highest rate.

CONCLUSIONS

Although the rate of surgery for cervical disc disease did not increase significantly during the 1990s, the rate of fusion procedures did rise significantly.

Retrospective cohort study of the clinical performance of 1-stage dental implants

PURPOSE

To evaluate long-term clinical performance of 1-stage dental implant prostheses at a single clinic, emphasizing clinical and demographic characteristics that affect implant survival.

MATERIALS AND METHODS

Dental records of all 308 patients (674 implants) treated with 1-stage implants at Mayo Clinic from October 1993 through May 2000 were reviewed from implant placement to last visit. Exposure and outcome variables affecting performance were collected separately to control bias in the data collection process. Additional confounding factors (age and sex) were adjusted with the stratified Cox proportional hazards model. Implant survival was determined by means of a Kaplan-Meier survival estimate. The log-rank test was used to determine the role of clinical and demographic variables in implant survival. The relative risk associated with the possible effect of clinical and demographic variables on implant survival was estimated with the Cox proportional hazards model.

RESULTS

The implant survival rate (n = 654 implants) was 97% (mean +/- SD follow-up, 21.0 +/- 18.8 months; range, 1 to 78 months). Performance bias was limited because nearly all patients were treated by 1 prosthodontist. Two implants failed after loading (6 and 9 months). The incidence of complications was less than 4%. Among the implant failures, use of heterogeneous bone graft was associated with 4.8 times more failures than was use of autogenous bone graft (P = .04). After augmentation, delaying implant placement for 5 to 6 months resulted in 8.6 times more failures than the rate after earlier placement (P < .001).

DISCUSSION

Retrospective review of the clinical performance of a 1-stage dental implant system yielded a 97% survival rate, with no failures noted after 13 months. Prosthetic complications were low, especially for fixed implant prostheses.

CONCLUSION

Clinical performance of 1-stage dental implant prostheses between 1993 and 2000 demonstrated a high level of predictability.

Is INFUSE bone graft superior to autograft bone? An integrated analysis of clinical trials using the LT-CAGE lumbar tapered fusion device

Multicenter human clinical studies of patients undergoing anterior lumbar fusion have been conducted using recombinant bone morphogenetic protein or rhBMP-2 on an absorbable collagen sponge, marketed as INFUSE Bone Graft, or autograft implanted in the LT-CAGE Lumbar Tapered Fusion device. An integrated analysis of multiple clinical studies was performed using an analysis of covariance to adjust for preoperative variables in a total of 679 patients. Of these patients, 277 had their cages implanted with rhBMP-2 on an absorbable collagen sponge and 402 received autograft transferred from the iliac crest. The patients treated with rhBMP-2 had statistically superior outcomes with regard to length of surgery, blood loss, hospital stay, reoperation rate, median time to return to work, and fusion rates at 6, 12, and 24 months. Oswestry Disability Index scores and the Physical Component Scores and Pain Index of the SF-36 scale at 3, 6, 12, and 24 months showed statistically superior outcomes in the rhBMP-2 group.

Treatment of multilevel cervical spondylotic myeloradiculopathy with posterior decompression and fusion with lateral mass plate fixation and local bone graft

This is a retrospective review of 32 patients with multilevel cervical myelopathy treated by laminectomy and lateral mass plate fusion. The prognosis of surgically treated myelopathy is evaluated as well as prognostic factors for recovery of myelopathy. Diagnoses included cervical spondylosis or ossification of the posterior longitudinal ligament. Final follow-up was at 15.2 months (mean) postoperatively. Myelopathy was graded preoperatively and postoperatively by the system of Nurick. All patients had preoperative radiographs and magnetic resonance imaging (MRI). The presence of abnormal T2-weighted MRI signal (myelomalacia) was noted. Postoperative studies included flexion-extension radiographs to assess fusion and MRI to evaluate decompression of neural elements and resolution of myelomalacia. Severity of preoperative Nurick myelopathy, presence of myelomalacia, and age were evaluated as potential prognostic indicators for surgically treated myelopathy. Mean Nurick score improved from 2.6 (range 1-4) to 1.8 (range 0-3) postoperatively (p < 0.0001). Twenty-two patients (71%) had improvement in Nurick grade of at least one point, and nine showed no improvement. No patients had deterioration of Nurick grade. Preoperative myelomalacia was noted in 15 (47%) patients, and all 15 had residual myelomalacia postoperatively. Severe myelopathy, age, and myelomalacia had no prognostic value for improvement of myelopathy. Complications included pseudarthrosis (3%), wound infection (9%), and transient C5 palsy (6%). This study demonstrates excellent outcomes from laminectomy and fusion in multilevel cervical myelopathy. A high rate of improvement of myelopathy was observed, neurologic deterioration did not occur, and complication rates were low. Severe myelopathy and myelomalacia on preoperative MRI had no prognostic value.

The use of poly-L-lactic acid in lumbar interbody cages: design and biomechanical evaluation in vitro

Cage design and cage material may play a crucial role in the incidence of postoperative complications reported with current non-absorbable interbody cage devices. Bioabsorbable poly-L-lactic acid cage devices may have potential benefits. The purpose of this study was to determine the required strength of poly-L-lactic acid cages for use in experimental goat studies and to evaluate the mechanical properties of different cage designs in situ. The yield and ultimate strength of native goat motion segments (L1-L6) were determined; the yield strength was used as a design parameter for the cages. The mechanical behaviour of two types of poly-L-lactic acid cages, the influence of endplate perforation, differences between toothed and smooth cages, and the influence of cage filling were biomechanically tested and compared to native motion segments. Only axial compression until failure of the motion segments was performed. Dual energy X-ray absorptiometry was used to determine bone mineral content. The yield and ultimate strength of the native motion segments were 3.5 and 7.0 kN, respectively. Based on these data, flexible and stiff poly-L-lactic acid cages were designed with strengths of 3.5 and 7 kN, respectively. Poly-L-lactic acid cages, whether with or without bone graft and perforating the endplates, did not reduce the compressive strength of motion segments as compared to native segments. However, toothed titanium cages, with the same geometry, negatively influenced the segments' compressive strength, which effect was reduced using smooth titanium cages.