Total Femur Replacement After Tumor Resection: Limb Salvage Usually Achieved But Complications and Failures are Common

Postoperative Outcomes of Total Femur Replacement in Oncologic and Nononcologic Patients: A Systematic Review of the Literature

BACKGROUND

Total femur replacement (TFR) is used for primary reconstruction after extensive tumor resection or as a revision surgery due to prosthetic failure. Studies on TFR rates of failure and functional outcomes are scarce. The purpose of our study was to compare the modes of failure, amputation rates, and functional outcomes after TFR between oncologic and nononcologic patients.

METHODS

We followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines were for this manuscript. Our study was registered on PROSPERO (413582). Quality assessment of all studies was performed using Strengthening the Reporting of Observational Studies in Epidemiology checklist. Endoprosthesis failure was assessed using the Henderson classification and functional outcomes using the Musculoskeletal Tumor Society score. Weighted means and standard deviations were calculated.

RESULTS

Overall failure rate was similar between groups. Henderson type 4 failures were more common within the nononcologic group, while the others were more frequently found in the oncologic group. Overall amputation rate was higher in the oncologic group mainly due to type 5 failure. Amputations occurred mainly after type 4 and type 5 failures. Functional outcome was better within the oncologic group (70.5 versus 61.7, respectively; P < .001).

CONCLUSIONS

Total femoral replacement in the oncologic and nononcologic group is associated with a high rate of failure (31% and 32.5%, respectively). Overall amputation rate was higher in the oncologic group mainly due to type 5 failure. Functional outcome was better within the oncologic group.

LEVEL OF EVIDENCE

Level III.

Extended distal femur resection: Megaprosthesis with telescopic bone allograft augmentation versus total femur prosthesis

BACKGROUND AND OBJECTIVE

Oncological distal femur resections can leave a proximal femur too short to host a stem. Reconstructive techniques are then challenging. The purpose of the study is to compare implant survival, complication rate and MSTS of two different options.

METHODS

We retrospectively divided 33 patients with primary bone tumours of distal femur in Group 1 (16 patients reconstructed with knee megaprosthesis with proximal bone augmentation, APC) and Group 2 (17 patients reconstructed with total femur prosthesis, TFP). Less than 12 cm of remaining proximal femur were planned for all resections.

RESULTS

MSTS score at 2 years is 25 ± 5 for Group 1 and 19 ± 7 for Group 2 (confidence interval [C.I.] 95%, p = 0.02). At 5 years it is 27 ± 2 for Group 1 and 22 ± 6 for Group 2 (C.I. 95%, p = 0.047). Failure and complication rates are lower for Group 1, but no statistical significance was reached. In APC reconstruction, union at the host-allograft junction was achieved in 16 out of 16 patients using the telescopic bone augmentation technique.

CONCLUSIONS

APC provides higher functional results compared to TFP after extended distal femur resection. In APC reconstruction, telescopic augmentation is excellent for achieving union at the host-allograft junction.

What Are the Complication Rates and Factors Associated With Total Femur Replacement After Tumor Resection? Findings From the Japanese Musculoskeletal Oncology Group

BACKGROUND

Patients undergoing massive tumor resection and total femur replacement (TFR) face a substantial risk of hip dislocation and infection, often resulting in multiple implant revisions or hip disarticulation. These complications can impact their independence and prognosis. Additionally, their shorter life expectancy is influenced by challenges in achieving local radical resection and controlling metastases. Identifying suitable candidates for TFR is vital, necessitating investigations into dislocation, infection, implant failure rates, local recurrence, overall survival, and associated factors.

QUESTIONS/PURPOSES

(1) What is the postsurgical complication (hip dislocation and infection) rate and factors associated with postsurgical complications in patients who underwent TFR after tumor resection? (2) What is the local recurrence rate, implant failure rate, overall survival rate, and factors associated with local recurrence and implant failure?

METHODS

We retrospectively evaluated 42 patients (median [range] age 47 years [10 to 79 years]) who underwent TFR and tumor resection at the time of the same surgical procedure between 1990 and 2020 at 12 registered institutions that specialized in tumor treatment in Japan. A total of 55% (23) of the patients were men, and 79% (33) had bone sarcoma. The median (range) follow-up period was 36.5 months (2 to 327 months). Of the 42 patients, 12% (5) were lost to follow-up before 2 years without meeting a study endpoint (postsurgical complications, revision, or amputation), and another 19% (8) died before 2 years with implants intact, leaving 69% (29) of the original group who had either follow-up of at least 2 years or met a study endpoint before the minimum surveillance duration. Another 10% (4) had a minimum of 2 years of follow-up but had not been seen in the past 5 years. Infection was defined as deep-seated infection involving soft tissues, bones, joints, and the area around the implant. We did not consider superficial infections. Implant failure was defined when a patient underwent reimplantation or amputation. The complication and implant failure rates were assessed by the cumulative incidence function method, considering competing events. The Kaplan-Meier method was used to estimate the overall survival rate.

RESULTS

The 1-month, 6-month, 1-year, and 2-year dislocation rates were 5%, 12%, 14%, and 14%, respectively. The 1-month, 6-month, 1-year, and 2-year infection rates were 5%, 7%, 10%, and 15%, respectively. Multivariable analyses for hip dislocation and infection revealed that resection of the abductor muscles and large tumor size were positively associated with hip dislocation. The 6-month, 1-year, and 2-year local recurrence rates were 5%, 15%, and 15%, respectively. The 6-month, 1-year, 2-year, and 5-year implant failure rates were 5% (95% confidence interval 1% to 15%), 7% (95% CI 2% to 18%), 16% (95% CI 6% to 29%), and 16% (95% CI 6% to 29%), respectively. Multivariable analyses of local recurrence and implant failure that led to reimplantation or amputation revealed that a positive surgical margin was positively associated with local recurrence. The 1-year, 2-year, and 5-year overall patient survival rates were 95% (95% CI 87% to 102%), 77% (95% CI 64% to 91%), and 64% (95% CI 48% to 81%), respectively.

CONCLUSION

Hip dislocation, infection, and local recurrence were frequently observed in patients who received massive tumor resection and TFR in our study, eventually leading to reimplantation or amputation. Preserving the abductor muscles and resecting the tumor with a wide margin can prevent postoperative dislocation and local recurrence. Future research should focus on patient selection criteria, prevention of hip dislocation, and innovative treatments.

LEVEL OF EVIDENCE

Level IV, therapeutic study.

Pathological fracture treated with total femoral replacement in a case of chondrosarcoma involving the entire-length femoral shaft

INTRODUCTION AND IMPORTANCE

We here present a case of chondrosarcoma of the diaphysis of the femur with extensive involvement of the length of the bone and with the pathological fracture at the mid-shaft level. Total femur replacement was done in this case with a bipolar head and repair of abductors and hip flexors to the implanted prosthesis.

CASE PRESENTATION

An elderly female in her late 60s presented to the trauma department with sudden onset pain and inability to bear weight on her left lower limb following a trivial slip and fall. The Radiographs revealed a pathological spiral mid-shaft displaced fracture of the femur with an extensive mixed lesion throughout the femur. Magnetic Resonance imaging revealed involvement of more than 90% of the femur with lesion extension into the quadriceps and hamstrings. Histopathology confirmed grade-II conventional chondrosarcoma. Metastatic work-up showed no distant spread. Wide-local resection and total femur endo-prosthetic reconstruction were done. No recurrence or infection was evident at the 18-month follow-up. In elderly non-metastatic pathological fractures, limb salvage with endo-prosthetic reconstruction can be a preferred treatment.

CLINICAL DISCUSSION

This case is unique in describing a rare presentation of chondrosarcoma of the diaphysis of the femur, which eventually landed in a pathological fracture. The fracture may increase the tumour's aggressiveness, but wide-margin resection should be the mainstay treatment for primary or recurrent chondrosarcoma, irrespective of pathological fracture.

CONCLUSION

In well-indicated cases (no distant spread - N0M0 disease), Total Femur Replacement (TFR) is an excellent option for limb salvage in tumours with extensive involvement of the femur.

Proximal Femur Replacements for an Oncologic Indication Offer a Durable Endoprosthetic Reconstruction Option: A 40-year Experience

BACKGROUND

Proximal femur replacements (PFRs) are an effective surgical option to treat primary and metastatic tumors causing large bony defects in the proximal femur. Given the relative rarity of these indications, current studies on PFR for oncologic indications are generally limited by patient volume or relatively short-term follow-up. Because recent advances in systemic therapy have improved the prognosis of patients who undergo limb salvage surgery for musculoskeletal tumors, data on the long-term durability of endoprosthetic reconstructions have become increasingly important.

QUESTIONS/PURPOSES

(1) How does the long-term survival of cemented bipolar PFRs compare with patient survival in patients who underwent PFR for benign, aggressive, and metastatic tumors? (2) What are common reasons for revisions of primary PFRs? (3) Which factors are associated with survival of primary PFRs? (4) What is the survivorship free from conversion of bipolar PFRs to THA?

METHODS

Between January 1, 1980, and December 31, 2020, we treated 812 patients with an endoprosthetic reconstruction for an oncologic indication. All patients who underwent a primary PFR for an oncologic indication were included in this study. The study cohort consisted of 122 patients receiving a primary PFR. Eighteen patients did not reach a censored endpoint such as death, revision, or amputation within 2 years. Thirty-three patients died within 2 years of their surgery. Of the 122 patients with primary PFRs, 39 did not reach a censored endpoint and have not been seen within the past 5 years. However, the mean follow-up time for these patients was longer than 10 years. The Social Security Death Index was queried to identify any patients who may have died but might not have been captured by our database To allow for adequate follow-up, endoprosthetic reconstructions performed after December 31, 2020 were excluded. The mean age at the time of the index surgery was 48 ± 22 years. The mean follow-up time of surviving patients was 7 ± 8 years. All PFRs were performed using a bipolar hemiarthroplasty with a cemented stem, and all implants were considered comparable. Demographic, oncologic, procedural, and outcome data including prosthesis survival, patient survival, complication rates, and rates of conversion to THA were analyzed. Patient, prosthesis, and limb salvage survival rates were generated, with implant revision as the endpoint and death as a competing risk. Statistical significance was defined as p < 0.05.

RESULTS

Generally, patients with benign or low-grade (Stage I) disease outlived their implants (100% patient survival through 30 years; p = 0.02), whereas the opposite was true in patients with high-grade, localized Stage II disease (64% patient survival at 5 years [95% CI 49% to 76%]; p = 0.001) or widespread Stage III metastatic disease (6.2% patient survival at 5 years [95% CI 0.5% to 24%]; p < 0.001). Primary PFR implant survival at 5, 10, 20, and 30 years was 97% (95% CI 90% to 99%), 81% (95% CI 67% to 90%), 69% (95% CI 46% to 84%), and 51% (95% CI 24% to 73%), respectively. Eight percent (10 of 122) of primary PFRs were revised for any reason. The most common causes of revision were aseptic loosening (3% [four of 122]), infection (3% [three of 122]), breakage of the implant (2% [two of 122]), and tumor progression (1% [one of 122]). Follow-up time was the only factor that was associated with revision of primary PFRs. Neither segment length nor stem length were associated with revision of primary. Six percent (seven of 122) of PFRs were converted to THA at a mean 15 ± 8 years from the index procedure. Survivorship free from conversion to THA (accounting for death as a competing risk) was 94% (95% CI 85% to 99%), 86% (95% CI 68% to 94%). and 77% (95% CI 51% to 91%) at 10, 20, and 30 years, respectively.

CONCLUSION

Cemented bipolar PFRs for an oncologic indication are a relatively durable reconstruction technique. Given the relative longevity and efficacy of PFRs demonstrated in our study, especially in patients with high-grade or metastatic disease where implant survival until all-cause revision was longer than patient survival, surgeons should continue to seriously consider PFRs in appropriate patients. The relative rarity of these reconstructions limits the number of patients in this study as well as in current research; thus, further multi-institutional collaborations are needed to provide the most accurate prognostic data for our patients.

LEVEL OF EVIDENCE

Level III, therapeutic study.

The outcomes of proximal femur replacement with hemiarthroplasty after tumor resection in individuals with Parkinson's disease

Background

Patients with neurological disorders often experience a high incidence of postoperative complications following proximal femur replacement (PFR) surgery. The orthopaedist faces a significant difficulty in treating Parkinson's disease (PD) because of the weakened bone condition, excessive muscle tension, and increased risk of fractures. The objective of this research is to assess the impact of PD on PFR following tumor removal.

Methods

A retrospective study was conducted from 2010 to 2020, focusing on a solitary institution, analyzing 9 patients diagnosed with PD who underwent PFR with hemiarthroplasty as a result of tumor removal. The study consists of 2 men and 7 women, with an average age of 71 (SD, 12) years. We assessed the outcomes after surgery in terms of pain management, quality of life, functional ability, occurrence of complications, and survival durations.

Results

All nine patients underwent planned surgeries. Intraoperative complications was not observed. The average length of the follow-up period was 24 (SD, 20) months, ranging from 8 to 72 months. Despite the fact that 8 patients passed away due to tumor progression, the endoprostheses were still well at that point. The preoperative VAS score of 7 (SD, 1.87) decreased to a postoperative score of 2 (SD, 1.32). The KPS was improved to73 (SD, 7) from 52 (SD, 14), postoperatively. Post-surgery, there were notable enhancements in both pain levels and the overall quality of life scores. Following the surgical procedure, individuals are able to ambulate steadily, resuming their regular daily routines. Living patients had an average MSTS score of 21 (SD, 2.5), ranging from 17 to 25. In total, there were four (44.4%) patients suffered complications after surgery, comprising of one wound dehiscence, one prosthetic fracture, one hip dislocation, and one local recurrence.

Conclusions

Significant improvements in function and pain relief can be achieved through PFR with hemiarthroplasty following tumor removal in patients with PD. The implementation of thorough preparation and carefull nursing results in reduced complications and improved outcomes in PD patients.

3D-printed custom-made short stem with porous structure for fixation of massive endoprosthesis in joint-preserving reconstruction after tumor resection

BACKGROUND

Large malignant bone tumors and revision limb salvage procedures often result in massive bone loss, leaving a short residual bone segment that cannot accommodate a standard stem for endoprosthesis fixation. Three-dimensional-printed (3DP) short stem with porous structure seems to be an alternative for short-segment fixation. This retrospective study aims to evaluate surgical outcomes, radiographical results, limb functions, and complications of using 3DP porous short stems in massive endoprosthesis replacement.

METHODS

Between July 2018 to February 2021, 12 patients with massive bone loss undergoing reconstruction with custom-made, short-stemmed massive endoprostheses were identified. Endoprosthesis replacement involved the proximal femur (n = 4), distal femur (n = 1), proximal humerus (n = 4), distal humerus (n = 1), and proximal radius (n = 2).

RESULTS

The mean percentage of resected bone was 72.4% of the whole length of the bone, ranging from 58.4 to 88.5%. The mean length of 3DP porous short stems was 6.3 cm. The median follow-up was 38 months (range, 22-58 months). The mean MSTS score was 89%, ranging from 77% to 93%. Radiographical assessment results showed bone in-growth to the porous structure in 11 patients, and the implants were well osseointegrated. Breakage of the 3DP porous short stem occurred in one patient intraoperatively. The patient developed aseptic loosening (Type 2) four-month after surgery and underwent revision with a plate applied to assist fixation. The implant survivorship was 91.7% at 2 years. No other complications were detected, such as soft-tissue failures, structural failures, infection, or tumor progression.

CONCLUSIONS

3DP custom-made short stem with porous structure is a viable method for fixation of the massive endoprosthesis in the short segment after tumor resection, with satisfactory limb function, great endoprosthetic stability, and low complication rates.

Preserving the rectus femoris and improving limb function after total femoral prosthesis replacement following resection of femoral malignant tumors

Background

Current research is focused on the factors that influence the maintenance of limb function after total femoral replacement. This retrospective study investigated the difference in functional outcomes in patients with invasion of the rectus femoris vs. an intact rectus femoris that underwent total femoral replacement with a modular total femur prosthesis.

Methods

The medical records of patients who underwent total femoral replacement with a modular total femur prosthesis between July 2010 and March 2017 at our institute were retrospectively reviewed. The patients were divided into two groups: group A had invasion of the rectus femoris and group B had an intact rectus femoris. Functional status was assessed using the Musculoskeletal Tumor Society Rating Scale (MSTS) and the Harris Hip Score (HHS). Complications were assessed using the International Society of Limb Salvage classification that was published in 2011 and modified in 2014.

Results

The mean total MSTS score (23.0 ± 4.8 vs. 17.6 ± 3.1; P = 0.02) and the mean total HHS score (80.17 ± 6.24 vs. 55.38 ± 13.30; P = 0.001) were significantly higher in patients with intact rectus femoris compared with patients with invasion of the rectus femoris. Patients with an intact rectus femoris achieved significantly better limb function (support and gait) and active range of motion (P &lt; 0.05). The overall complication rate was 35.7%.

Conclusions

Functional outcomes after total femoral replacement were significantly better in patients with an intact rectus femoris compared with patients with invasion of the rectus femoris, possibly because more muscle mass can be preserved around the femur in patients with an intact rectus femoris.

Infections of Tumor Prostheses: An Updated Review on Risk Factors, Microbiology, Diagnosis, and Treatment Strategies

Several causes contribute to the high infection rate in tumor prostheses, including extensive tissue dissection and patients' immunosuppression due to the neoplastic disease. Most of these infections develop within the first 2 years following surgery with 70% of them occurring during the first year, while they are often associated with a low pathogen burden. The pathogenesis of infections in tumor prostheses is linked to bacteria developing in biofilms. Approximately half of them are caused by Staphylococcus spp., followed by Streptococcus spp., Enterococcus spp., and Enterobacteriaceae spp., while multiple pathogens may be isolated in up to 25% of the cases, with coagulase-negative Staphylococci (CoNS) and Enterococccus spp. being the most frequent pair. Although early detection and timely management are essential for complete resolution of these challenging infections, prompt diagnosis is problematic due to the highly varying clinical symptoms and the lack of specific preoperative and intraoperative diagnostic tests. Surgical management with one- or two-stage revision surgery is the mainstay for successful eradication of these infections. The recent advances in laboratory diagnostics and the development of biofilm-resistant prostheses over the past years have been areas of great interest, as research is now focused on prevention strategies. The aim of this study is to review and consolidate the current knowledge regarding the epidemiology, risk factors, microbiology, and diagnosis of infections of tumor prostheses, and to review the current concepts for their treatment and outcomes.

Contribution of Sonication to the Identification of Megaprosthesis Infection in Culture Negative Oncologic Patient

Conventional central osteosarcoma mainly affects the metaphysis of long bones in young people. The use of megaprostheses in oncological patients has increased in recent years. However, this type of surgery is not exempt from complications, with infections being the most common. In recent years, the presence of biofilm-forming bacteria has increased. Biofilm characteristics allow bacteria to resist hostile environmental conditions. The application of long wave ultrasound (process known as sonication) on the rescued inert material before culture interrupts the biofilm and generates a significantly higher recovery of bacterial growth compared to conventional tissue culture. We present the case of a 12-year-old patient with osteosarcoma of the femur, who, after surgery, developed a prosthetic infection detected by sonication, with negative soft tissue culture.

Hip-preserving reconstruction using a customized cemented femoral endoprosthesis with a curved stem in patients with short proximal femur segments: Mid-term follow-up outcomes

Background

Short metaphyseal segments that remain following extensive distal femoral tumor resection can be challenging to manage, as the residual short segments may not be sufficient to accept an intramedullary cemented stem of standard length. The present study was developed to detail preliminary findings and experiences associated with an intra-neck curved stem (INCS) reconstructive approach, with a particular focus on mechanical stability.

Method

From March 2013 to August 2016, 11 total patients underwent reconstructive procedures using a customized cemented femoral endoprosthesis (CCFE) with an INCS. Measurements of femoral neck-shaft angle values were made before and after this procedure. Radiological outcomes associated with this treatment strategy over an average 63-month follow-up period were additionally assessed. Functionality was assessed based upon Musculoskeletal Tumor Society (MSTS) scores, while a visual analog scale (VAS) was used to rate pre- and postoperative pain, and any complications were noted.

Results

Relative to the preoperative design, no significant differences in femoral neck–shaft angle were observed after this reconstructive procedure (p = 0.410). Postoperatively, the tip of the stem was primarily positioned within the middle third of the femoral head in both lateral and posterior-anterior radiographic, supporting the accuracy of INCS positioning. The average MSTS score for these patients was 25 (range: 21–28), and VAS scores were significantly reduced after surgery (p &lt; 0.0001). One patient exhibited local disease recurrence and ultimately succumbed to lung metastases, while two patients exhibited aseptic loosening. None of the treated patients exhibited complications such as infections, periprosthetic fractures, or prosthetic fractures as of most recent follow-up.

Conclusion

CCFE with an INCS represents a viable approach to massive femoral diaphyseal defect with short proximal femur repair, as patients can achieve good functional outcomes and early weight-bearing with proper individualized rehabilitative interventions, all while exhibiting low rates of procedure-related complications.

A comparison of cemented and cementless intra-neck curved stem use during hip-preserving reconstruction following massive femoral malignant tumor removal

Background

Patients who undergo massive femoral malignant tumor (MFMT) resection often exhibit shortened femoral metaphyseal juxta-articular segments. The use of a customized femoral endoprosthesis (CFE) with an intra-neck curved stem (INCS) has emerged as a viable reconstructive surgical strategy for these individuals. Relative to a cemented INCS, it remains unclear as to whether cementless INCS use is associated with improvements in functionality or reconstructive longevity. As such, the present study was conducted to compare functional outcomes, endoprosthetic survival, and endoprosthesis-related complication rates in patients undergoing cemented and cementless INCS implantation.

Methods

A total of 24 patients undergoing lower limb salvage and reconstructive surgical procedures utilizing cemented or cementless INCS endoprostheses were retrospectively included. Patient-functional outcomes, endoprosthetic survival, and complication rates were compared as a function of age; diagnosis; the length of femoral resection; residual proximal femur length; Musculoskeletal Tumor Society (MSTS) scores; visual analog scale (VAS) scores; and the rates of implant breakage, periprosthetic infections, periprosthetic fractures, and aseptic loosening.

Results

The mean follow-up was 56 months. Significant differences in the length of femoral resection (p&lt;0.001) and residual proximal femur length were observed (p&lt;0.001) between the cemented and cementless INCS groups. There were no differences in overall patient survival and aseptic loosening-associated endoprosthesis survival in the cemented and cementless groups. None of the included patients experienced periprosthetic fractures, infections, or implant breakage. Average respective MSTS and VAS scores did not differ between groups.

Conclusion

For patients undergoing treatment for MFMTs, the use of a CFE with an INCS has emerged as a viable approach to hip-preserving reconstructive surgery. With appropriately designed individualized rehabilitative programs, good functional outcomes can be achieved for these endoprostheses, which are associated with low complication rates. Moreover, the selection between cemented or cementless INCS in the clinic should be made based on patient-specific factors, with cementless INCS implementation being preferable in younger patients with good-quality bone, the potential for long-term survival, and the osteotomy site near the lesser trochanter, whereas cemented INCS use should be favored for individuals who are older, have a shorter life expectancy, or have poor bone quality.

Additive manufactured polyether-ether-ketone implants for orthopaedic applications: a narrative review

Polyether-ether-ketone (PEEK) is believed to be the next-generation biomedical material for orthopaedic implants that may replace metal materials because of its good biocompatibility, appropriate mechanical properties and radiolucency. Currently, some PEEK implants have been used successfully for many years. However, there is no customised PEEK orthopaedic implant made by additive manufacturing licensed for the market, although clinical trials have been increasingly reported. In this review article, design criteria, including geometric matching, functional restoration, strength safety, early fixation, long-term stability and manufacturing capability, are summarised, focusing on the clinical requirements. An integrated framework of design and manufacturing processes to create customised PEEK implants is presented, and several typical clinical applications such as cranioplasty patches, rib prostheses, mandibular prostheses, scapula prostheses and femoral prostheses are described. The main technical challenge faced by PEEK orthopaedic implants lies in the poor bonding with bone and soft tissue due to its biological inertness, which may be solved by adding bioactive fillers and manufacturing porous architecture. The lack of technical standards is also one of the major factors preventing additive-manufactured customised PEEK orthopaedic implants from clinical translation, and it is good to see that the abundance of standards in the field of additive-manufactured medical devices is helping them enter the clinical market.

Total femur replacement with 18 years of follow-up: A case report

BACKGROUND

Osteosarcoma is one of the most common primary malignant bone tumors and is more common in adolescents. The femur is the most common site of osteosarcoma, and many patients require total femur replacement. We reviewed the relevant literature and case findings, summarized and analyzed this case in combination with relevant literature, and in doing so improved the understanding of the technology.

CASE SUMMARY

The case we report was a 15-year-old patient who was admitted to the hospital 15 days after the discovery of a right thigh mass. The diagnosis was osteosarcoma of the right femoral shaft. After completion of neoadjuvant chemotherapy and preoperative preparation, total right femoral resection + artificial total femoral replacement was performed. Then, chemotherapy was continued after surgery. The patient recovered well after treatment, and the function of the affected limb was good. No recurrence, metastasis, prosthesis loosening, dislocation, fracture or other complications were found during 18 years of follow-up. At present, the patient can still work and lives normally. The results of the medium- and long-term follow-up were satisfactory.

CONCLUSION

Artificial total femur replacement is a feasible limb salvage operation for patients with femoral malignant tumors, and the results of medium- and long-term follow-up are satisfactory.

Application of Endoprosthetic Replacement in Old Patients with Isolated Proximal Femoral Bone Metastases

BACKGROUND

Due to radical resection, endoprosthetic reconstruction (EPR) is more invasive and increases the risk of dislocation. Therefore, the suitability of EPR for elderly patients with metastatic tumor needs further investigation.

METHODS

Seventy-one adult patients with isolated proximal femoral bone metastases who underwent EPR were retrospectively analyzed and stratified into two groups: elderly age group (≥60 years, n = 31) and younger age group (<60 years, n = 40). The effect of age on prognosis was analyzed to determine whether EPR is beneficial in elderly patients with proximal femoral metastatic tumor. Cox regression modeling was used to evaluate the effect of different factors on postoperative survival outcomes.

RESULTS

Ten (32.26%) and 9 (22.50%) cases of perioperative complications were recorded in the elderly and younger age groups, respectively, with median survival times of 22.00 ± 4.61 months and 23.00 ± 2.85 months, respectively; a log-rank test showed that the difference was not statistically significant (p = 0.657). A Cox regression model was established with patient age as the covariable to evaluate whether it affected postoperative survival. The risk of death due to age was not significant (p = 0.649), but malignancy and femoral metastasis type were significantly associated with postoperative survival (p = 0.001 and p = 0.019).

CONCLUSION

Although older patients have a slightly higher incidence of postoperative complications than younger patients, they do not experience severe adverse consequences. With rigorous selection and careful preparation, EPR is appropriate for the treatment of proximal femoral metastases in older patients, including those with Harrington type I-II acetabular invasion.

Hip-Preserved Reconstruction Using a Customized Cementless Intercalary Endoprosthesis With an Intra-Neck Curved Stem in Patients With an Ultrashort Proximal Femur: Midterm Follow-Up Outcomes

Background: Hemiarthroplasty is widely used for proximal femoral reconstruction after tumor resection. However, complications of hemiarthroplasty include infection, hip dislocation, and acetabular wear. This study aimed to: (1) evaluate the reliability and validity of a customized cementless intercalary endoprosthesis (CCIE) with an intra-neck curved stem (INCS) to reconstruct femoral diaphyseal defects with an ultrashort proximal femur (UPF); (2) assess the lower extremity function after reconstruction with this endoprosthesis; and (3) identify the postoperative complications associated with the use of this endoprosthesis.

Methods: Between October 2015 and May 2019, 13 patients underwent reconstruction with a CCIE with an INCS. The distance from the center of the femoral head to the midline of the body and the apex of the acetabulum was measured preoperatively. Additionally, the distance from the tip of the INCS to the midline of the body and the apex of the acetabulum was measured postoperatively. The femoral neck–shaft angle was also measured pre- and postoperatively. After an average follow-up duration of 46 months, the radiological outcomes of the CCIE with an INCS were analyzed. Function was evaluated with the Musculoskeletal Tumor Society (MSTS) score. Pain was measured using a paper visual analog scale (VAS) pre- and postoperatively, and complications were recorded.

Results: Compared with our preoperative design, we found no significant difference in the postoperative distance from the tip of the INCS to the body midline (p = 0.187) and the apex of the acetabulum (p = 0.159), or in the postoperative femoral neck–shaft angle (p = 0.793). Thus, the INCS positions were deemed accurate. The average MSTS score was 26 (range: 24–28), and the VAS score was significantly decreased postoperatively compared with preoperatively (p < 0.0001). No patients developed aseptic loosening, infection, periprosthetic fracture, or prosthetic fracture as of the last follow-up.

Conclusion: The CCIE with an INCS was a valid and reliable method for reconstructing femoral diaphyseal defects with a UPF following malignant tumor resection. Postoperative lower extremity function was acceptable, with an appropriate individualized rehabilitation program, and the incidence of complications was low.

Implant Survival, Clinical Outcome and Complications of Megaprosthetic Reconstructions Following Sarcoma Resection

Simple Summary

Malignant bone and soft tissue tumors are usually surgically removed with an envelope of healthy tissue as a barrier. If located in the long bones of the upper and lower extremity, this approach leads to a large bone defect commonly affecting a joint. One way to rebuild the bone defect and the neighboring joint is the use of a megaprosthesis that is anchored in the remaining bone comparable to a conventional joint replacement. In general this approach is popular as it provides early stability and allows the affected patient to begin rehabilitation early on. However, complications leading to long-term unplanned reoperation are common. This article provides an overview of current implant survival, types of complication and long-term outcomes of megaprostheses used following tumor resection.

Abstract

Megaprosthetic reconstruction of segmental bone defects following sarcoma resection is a frequently chosen surgical approach in orthopedic oncology. While the use of megaprostheses has gained popularity over the last decades and such implants are increasingly used for metastatic reconstructions and in non-tumor cases, there still is a high risk of long-term complications leading to revision surgery. This article investigates current implant survivorship, frequency and types of complications as well as functional outcomes of upper and lower limb megaprosthetic reconstructions.

What Is the Survival of the Telescope Allograft Technique to Augment a Short Proximal Femur Segment in Children After Resection and Distal Femur Endoprosthesis Reconstruction for a Bone Sarcoma?

BACKGROUND

Large, malignant bone tumors and revision limb salvage procedures often result in the resection of extensive lengths of the involved bone segment, leaving a residual segment of bone that may be too short to support a standard intramedullary stem for endoprosthetic reconstruction. Telescope allografting, in which an allograft is used to augment the remaining bone segment by telescoping it into the residual bone segment, was described for situations in which residual bone stock is insufficient after tumor resection or prosthetic revision. Apart from one study that first described the procedure [15], there are no other studies reporting the outcome of this telescopic concept for restoring bone stock.

QUESTIONS/PURPOSES

For patients younger than 18 years who underwent the telescopic allograft technique to augment a short segment of the proximal femur after resection of bone sarcomas who also underwent endoprosthesis reconstruction of the distal femur, we asked: (1) What is the survivorship free from removal of the telescopic allograft and the endoprosthetic stem at 7 years after surgery? (2) What proportion of these reconstructions will heal to the host bone without delayed union or nonunion? (3) What is the functional outcome based on the Musculoskeletal Tumor Society (MSTS) score?

METHODS

We retrospectively studied our institutional database and identified 127 patients younger than 18 years who underwent surgery for a primary malignant bone tumor of the distal femur between December 2008 and October 2018. After excluding 16 patients undergoing amputation and rotationplasty and 57 patients undergoing recycled autograft/allograft reconstruction, 54 patients who underwent primary or revision distal femur endoprosthesis reconstruction were identified. Among these patients, we considered 15 patients who underwent telescopic allograft augmentation of the femur for analysis. One patient was lost to follow-up before 2 years but was not known to have died, leaving 14 for analysis at a median (range) 49 months (24 to 136 months) of follow-up. The indications for telescopic allograft augmentation of the femur in our institution were a proximal femur length of less than 120 mm after resection or resection of more than two-thirds of the total length of the femur. Ten of 14 patients underwent telescopic allograft augmentation as a revision procedure (distal femur resorption in five patients, endoprosthesis stem loosening in three patients, implant fracture in one patient, and infection in one patient), and the remaining four patients underwent telescopic allograft augmentation as a primary limb salvage procedure for large malignant bone tumors of the distal femur. The histologic diagnosis in all patients was osteosarcoma. At the time of telescopic allograft augmentation and reconstruction, the median age of the patients was 14 years (7 to 18 years). The size and the type of bone allograft to be used (femoral shaft or proximal femur) was planned before surgery, with consideration of the extent of resection, level of osteotomy, diameter of the host bone at the osteotomy site, and approximate diameter of the endoprosthesis stem to be used. The segment of the cylindrical allograft used for telescoping was thoroughly washed, prepared, and impacted onto the native femur to achieve telescoping and overlap. Serial digital radiographs were performed once a month for the first 6 months after the procedure, every 2 months until 1 year, and then every 6 months thereafter. Two surgeons in the department (at least one of which was involved in the surgery) retrieved and reviewed clinical notes and radiographs to determine the status of the telescopic allograft and endoprosthesis stem. We defined delayed union as radiological union at the osteotomy site more than 6 months after the procedure without additional surgery; we defined nonunion as no radiological evidence of callus formation at the osteotomy site 9 months after the procedure, necessitating additional surgery. The reviewers did not disagree about the definition of healing time. None of the patients missed radiographic follow-up. Kaplan-Meier survivorship free from removal of telescopic allograft and the endoprosthesis stem at 7 years after surgery was estimated. Patient function was assessed using the 1993 version of the MSTS [9], as determined by chart review of the institutional database performed by one of the surgeons from the department.

RESULTS

The survivorship free from removal of the telescopic allograft and endoprosthesis stem at 7 years after surgery was 80% (95% confidence interval 22% to 96%). The allograft united with the host bone in 100% (14 of 14) of the patients. Though 21% (3 of 14) had delayed union, no nonunions were seen. The median (range) MSTS score at the final follow-up interval was 27 (22 to 30).

CONCLUSION

Although this is a small group of patients, we believe that allograft segments help augment short bone stock of the proximal femur after long-segment resections, and the telescopic technique seems to be associated with a low proportion of nonunion or delayed union, which is one of the most common complications of allografts. Maintaining an adequate length of the proximal femur is important in preserving the hip, and this technique may be especially useful for young individuals who may undergo repeated revision procedures.

LEVEL OF EVIDENCE

Level IV, therapeutic study.

Clinical outcomes of endoprosthetic reconstruction for proximal femoral resection

INTRODUCTION

The proximal femur is a common site for primary sarcomas and metastatic lesions. Although the early results of tumor prostheses are promising, the long-term results of reconstruction are unknown. The purpose of this study is to evaluate the prognostic factors affecting prosthesis survival and complications after proximal femoral resection and reconstruction.

METHODS

We reviewed the results of 68 patients who underwent proximal femoral resection and reconstruction with a modular bipolar-type tumor prosthesis between 2005 and 2017. The mean follow-up was 55.6 months (range 6-172 months). There were 50 male and 18 female patients with a mean age of 41.5 years (range 11-80 years). Cumulative survival analysis was performed to analyze the risk factors of prosthesis survival. We also evaluated the complications after operation.

RESULTS

Fourteen (21%) patients required further surgery at a mean 37 months post-operatively (range 5-125 months). There were three cases of infection (4%), six of local recurrence (9%), three of acetabular erosion (4%) and two of stem loosening (3%). The implant survival rates were 83.9% at 5 years and 59.8% at 10 years. Prosthesis survivals did not differ based on fixation method (P = 0.085), age (P = 0.329) or resection length (P = 0.61). Acetabular chondrolysis was identified in 18 (26%) patients and longer resection length (≥20 cm) showed a trend for risk of acetabular wear (P = 0.132).

CONCLUSION

The results of proximal femoral resection and reconstruction with a modular bipolar-type prosthesis were found to be acceptable with infection and local recurrence as short-term complications and loosening and acetabular erosion as long-term complications.

Surgical treatment for patients with hemophilic pseudotumor-related femoral fracture: a retrospective study

BACKGROUND

Hemophilic pseudotumor (HPT)-related fracture is a rare but severe complication in patients with HPTs. These fractures often occur in femurs. There is no consensus on the standard surgical protocol for HPT-related femoral fracture. The present retrospective study evaluated the outcomes of these patients treated with surgical interventions.

METHODS

Ten patients with HPT-related femoral fractures who were treated with 14 surgical procedures due to 11 fractures in our hospital from January 2014 to April 2020 were evaluated retrospectively. Demographic data, fracture location, complications after surgery, and follow-up outcomes were recorded and analyzed. The mean follow-up period was 39.7 months.

RESULTS

The mean age at surgery was 31 years. Closed reduction external fixation (CREF) was originally performed in 2 patients, open reduction internal fixation (ORIF) was performed in 4 patients, screw fixation alone was performed in 1 patient, brace immobilization was performed in 1 patient, and amputation was performed in 3 patients. Bone union was observed in 5 patients, and an adequate callus was visible in 2 patients. Both patients with CREF had pin infections. Nonunion combined with external fixation (EF) failure occurred in 1 patient, and the plate was broken after ORIF. Three patients underwent autogenous or allogeneic cortical strut grafting. Three patients had HPT recurrence.

CONCLUSIONS

It is necessary to perform surgery in patients with HPT-related femoral fractures. Surgical treatments must consider fracture stabilization and HPT resection. Internal fixation is preferable, and EF should only be used for temporary fixation. If the HPT erodes more than one third of the bone diameter, strut grafts are necessary for mechanical stability. Amputation is an appropriate curative method in certain situations.

Onlay fibula autografting technique and its comparison with cortical allograft for the reconstruction of periprosthetic bone defects around the femur

BACKGROUND

Bone defect around the femur related to revisions or periprosthetic fractures (PFF) is an issue. We present a bone defect reconstruction technique in femoral revisions and/or PFF using fibula autograft and compared our radiological and clinical results to that of allograft.

METHODS

A total of 53 patients who underwent revision hip arthroplasty and/or PFF fixation with the use of cortical fibula autograft (FG group) or cortical allograft (CG group) were evaluated. After exclusions, 20 patients who had minimum two years of follow-up were investigated for each group, for their radiological and clinical outcomes.

RESULTS

In FG and CG groups, the median ages were 69.5(44-90) and 62(38-88) years, follow-ups were 59(28-72) and 120(48-216) months, defect lengths were seven (1-10) and ten (1-17) cm, and grafts lengths were 16.5(10-30) and 20(12-37) cm, respectively. The rate of graft incorporation was 90% in each group and median time to incorporations were seven (4-12) and 12(6-24) months (p < 0.001), and graft resorption (moderate and severe) rates were 10% and 25% (p = 0.41), respectively. Median Harris Hip (77.6 vs 78.0), WOMAC (23.2 vs 22), SF-12 physical (50.0 vs 46.1), and SF-12 mental (53.8 vs 52.5) scores were similar between the groups, respectively. Kaplan-Meier survivorship analyses revealed an estimated mean survival of 100% at six years in FG group and 90% at 14 years in CG group.

CONCLUSION

In the reconstruction of periprosthetic bone defects after femoral revision or PPF, onlay cortical fibula autografts provide comparable clinical and radiological outcomes to allografts. Its incorporation is faster, it is cost-effective and easy to obtain without apparent morbidity.

Salvage of Distal Femoral Replacement Loosening with Massive Osteolysis Using Impaction Grafting: A Report of 2 Cases

CASE

Salvage of 2 cases of distal femoral replacement loosening with massive osteolysis using impaction grafting are presented with 9- and 11-year follow-ups.

CONCLUSION

Surgeons should keep impaction grafting in their armamentarium for cases of failed DFR with severe osteolysis. Doing so may allow for preservation of the native hip and deferment of more radical procedures (i.e. total femur replacement) that have high rates of complication and poor survivorship.

Nonmechanical Revision Indications Portend Repeat Limb-Salvage Failure Following Total Femoral Replacement

BACKGROUND

There is scant evidence to guide decision-making for patients considering total femoral replacement (TFR). We aimed to identify the indication, patient, disease, and surgical technique-related factors associated with failure. We hypothesized that failure occurs more frequently in the setting of revision surgical procedures, with infection as the predominant failure mode.

METHODS

We performed a retrospective cohort study of patients receiving total femoral endoprostheses for oncological and revision arthroplasty indications; 166 patients met these criteria. Our primary independent variable of interest was TFR for a revision indication (arthroplasty or limb salvage); the primary outcome was failure. Analyses were performed for patient variables (age, sex, diagnosis group, indication), implant variables (model, decade, length, materials), and treatment variables. We analyzed TFR failures with respect to patient factors, operative technique, and time to failure. We conducted bivariate logistic regressions predicting failure and used a multivariate model containing variables showing bivariate associations with failure.

RESULTS

Forty-four patients (27%) had treatment failure. Failure occurred in 24 (23%) of 105 primary TFRs and in 20 (33%) of 61 revision TFRs; the difference was not significant (p = 0.134) in bivariate analysis but was significant (p = 0.044) in multivariate analysis. The mean age at the time of TFR was 37 years in the primary group and 51 years in the revision group (p = 0.0006). Of the patients who had mechanical failure, none had reoccurrence of their original failure mode, whereas all 8 patients from the nonmechanical cohort had reoccurrence of the original failure mode; this difference was significant (p = 0.0001).

CONCLUSIONS

TFR has a high failure rate and a propensity for deep infection, especially in the setting of revision indications and prior infection. All failed TFRs performed for revision indications for infection or local recurrence failed by reoccurrence of the original failure mode and resulted in amputation.

LEVEL OF EVIDENCE

Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Long term outcomes of total humeral replacement for oncological reconstructions: A single institution experience

BACKGROUND

There is a paucity of data on long-term survivorship and outcomes for total humerus replacements (THR) with only two series reporting 10-year survival.

PATIENTS AND METHODS

A review of 769 consecutive, prospectively collected endoprosthetic reconstructions for oncological diagnoses at a single-center between 1980 and 2019 was performed. Patients with THRs were isolated and analyzed for outcomes, complications, and modes of failure.

RESULTS

Eighteen patients with 20 THR implants were identified. The median follow-up for surviving patients was 148 months (interquartile range [IQR] = 74-194) and 60 months (IQR = 17-155 months) for all patients. Two prostheses required revision for failure, both for symptomatic shoulder dislocation. There were three local recurrences. Revision-free survival at 5, 10, and 15 years was 100%, 86% and 86%, respectively. There were no cases of ulnar component failure, radial nerve palsy, or periprosthetic infection.

CONCLUSIONS

THR prosthesis survivorship is comparable to the previous series, with a longer follow-up than has previously been reported. Symptomatic shoulder instability was common (25%), and was the only cause of revision. Reverse total shoulder could be an important way to address this in the future. Local recurrence rates were high, as has been reported elsewhere for THR.

Outcomes of Expandable Prostheses for Primary Bone Malignancies in Skeletally Immature Patients: A Systematic Review and Pooled Data Analysis

BACKGROUND

Osteosarcoma and other primary bone malignancies are relatively common in skeletally immature patients. Current literature features case series with disparate complication rates, making it difficult for surgeons to educate patients on outcomes after limb salvage with expandable prostheses. This study aims to provide an update on complication rates, mortality, and functional outcomes in patients who undergo limb salvage with expandable prostheses for primary bone malignancies.

METHODS

A systematic review was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. An exhaustive PubMed/Medline and Cochrane search of peer-reviewed published literature from 1997 to 2017 was performed, yielding a total of 1350 studies. After multiple rounds of review for inclusion and exclusion criteria, 28 retrospective studies were included. All were level IV evidence of case series and retrospective studies. Overall, this included 634 total patients and 292 patients with individual patient data. The primary outcomes studied were complication rates, mortality, and Musculoskeletal Tumor Society (MSTS) functional score. Secondary outcomes included complication rate subtypes, number of lengthening procedures, mean amount lengthened, and prevalence of limb length discrepancies.

RESULTS

A total of 292 patients with individual patient data averaged 10.1 years at the surgery and had a mean follow-up of 67 months. Two hundred sixteen patients (74%) had tumors of the distal femur. MSTS scores averaged 80.3 and overall mortality was 22%. Patients with distal femur tumors averaged 4.4 lengthening procedures and 43 mm lengthened. Leg length discrepancy (LLD) was 36% overall, which increased with longer periods of follow-up (P<0.001). Overall complication and revision rate was 43%, increasing to 59% in patients with 5 to 10 years of follow-up, and 89% in patients with >10 years of follow-up. Minimally invasive prostheses had lower rates of complications than noninvasive prostheses (P=0.024), specifically mechanical complications (P=0.028), mostly because of increased rates of lengthening and device failure in the noninvasive models (21% vs. 4%, P=0.0004).

CONCLUSIONS

Despite its limitations, which include entirely heterogenous and retrospective case series data, this systematic review provides clinicians with pooled summary data representing the largest summary of outcomes after reconstruction with expandable prostheses to date. This analysis can assist surgeons to better understand and educate their patients and their families on functional outcomes, mortality, and complication rates after limb-sparing reconstruction with expandable prostheses for primary bone malignancies.

LEVEL OF EVIDENCE

Level IV-retrospective case series with pooled data.

Limb salvage reconstruction: Radiologic features of common reconstructive techniques and their complications

Limb salvage surgery refers to orthopaedic procedures designed to resect tumors and reconstruct limbs. Improvements in managing malignant bone lesions have led to a dramatic shift in limb salvage procedures. Orthopaedic surgeons now employ four main reconstructive procedures: endoprosthesis, autograft, bulk allograft, and allograft prosthetic composite. While each approach has its advantages, each technique is associated with complications. Furthermore, knowledge of procedure specific imaging findings can lead to earlier complication diagnosis and improved clinical outcomes. The aim of this article is to review leading reconstructive options available for limb salvage surgery and present a case series illustrating the associated complications.

Limb Salvage and Reconstruction Options in Osteosarcoma

Advances in chemotherapy, sophisticated imaging, and surgical techniques over the last few decades have allowed limb-salvage surgery (LSS) to become the preferred surgical treatment for bone sarcomas of the extremities. The goal of LLS is to maximize limb functionality to allow for the maintenance of quality of life without compromising overall survival and tumor local recurrence rates. Today, limb-salvage procedures are performed on 80-95% of patients with extremity osteosarcoma, and the 5-year survival rate in extremity osteosarcoma patients is now 60-75%.This chapter will focus on LSS for extremity osteosarcoma. Common types of surgical reconstruction techniques including endoprostheses, intercalary or osteoarticular allografts, vascularized fibular autografts, and allograft prosthetic composites (APC), and their complications such as infection, local recurrence, graft fracture, implant failure, and nonunion will be discussed in detail. Anatomic locations of lesions discussed include the proximal femur, distal femur, proximal tibia, distal tibia, proximal humerus, distal humerus, and forearm bones.

What is the Likelihood That Tumor Endoprostheses Will Experience a Second Complication After First Revision in Patients With Primary Malignant Bone Tumors And What Are Potential Risk Factors?

BACKGROUND

Endoprosthetic reconstruction of massive bone defects has become the reconstruction method of choice after limb-sparing resection of primary malignant tumors of the long bones. Given the improved survival rates of patients with extremity bone sarcomas, an increasing number of patients survive but have prosthetic complications over time. Several studies have reported on the outcome of first endoprosthetic complications. However, no comprehensive data, to our knowledge, are available on the likelihood of an additional complication and the associated risk factors, despite the impact of this issue on the affected patients.

QUESTIONS/PURPOSES

(1) What are the types and timing of complications and the implant survivorship free from revision after the first complication? (2) Does survivorship free from repeat revision for a second complication differ by anatomic sites? (3) Is the type of first complication associated with the risk or the type of a second complication? (4) Are patient-, tumor-, and treatment-related factors associated with a higher likelihood of repeat revision?

METHODS

Between 1993 and 2015, 817 patients underwent megaprosthetic reconstruction after resection of a tumor in the long bones with a single design of a megaprosthetic system. No other prosthetic system was used during the study period. Of those, 75% (616 of 817) had a bone sarcoma. Seventeen patients (3%) had a follow-up of less than 6 months, 4.5% (27 of 599) died with the implant intact before 6 months and 43% (260 of 599 patients) underwent revision. Forty-three percent of patients (260 of 599) experienced a first prosthetic complication during the follow-up period. Ten percent of patients (26 of 260) underwent amputation after the first complication and were excluded from further analysis. Second complications were classified using the classification of Henderson et al. to categorize surgical results. Briefly, this system categorizes complications as wound dehiscence (Type 1); aseptic loosening (Type 2); implant fractures or breakage and periprosthetic fracture (Type 3); infection (Type 4); and tumor progression (Type 5). Implant survival curves were calculated with the Kaplan-Meier method and compared using the log-rank test. Hazard ratios (HR) were estimated with their respective 95% CIs in multivariate Cox regression models.

RESULTS

A second complication occurred in 49% of patients (115 of 234) after a median of 17 months (interquartile range [IQR] 5 to 48) after the surgery for the first complication. The time to complication did not differ between the first (median 16 months; IQR 5 to 57) and second complication (median 17 months; IQR 5 to 48; p = 0.976). The implant survivorship free from revision surgery for a second complication was 69% (95% CI 63 to 76) at 2 years and 46% (95% CI 38 to 53) at 5 years. The most common mode of second complication was infection 39% (45 of 115), followed by structural complications with 35% (40 of 115). Total bone and total knee reconstructions had a reduced survivorship free from revision surgery for a second complication at 5 years (HR 2.072 [95% CI 1.066 to 3.856]; p = 0.031) compared with single joint replacements. With the numbers we had, we could not show a difference between the survivorship free of revision for a second complication based on the type of the first complication (HR 0.74 [95% CI 0.215 to 2.546]; p = 0.535). We did not detect an association between total reconstruction length, patient BMI, and patient age and survivorship free from revision for a second complication. Patients had a higher risk of second complications after postoperative radiotherapy (HR 1.849 [95% CI 1.092 to 3.132]; p = 0.022) but not after preoperative radiotherapy (HR 1.174 [95% CI 0.505 to 2.728]; p = 0.709). Patients with diabetes at the time of initial surgery had a reduced survivorship free from revision for a second complication (HR 4.868 [95% CI 1.497 to 15.823]; p = 0.009).

CONCLUSIONS

Patients who undergo revision to treat a first megaprosthetic complication must be counseled regarding the high risk of future complications. With second complications occurring relatively soon after the first revision, regular orthopaedic follow-up visits are advised. Preoperative rather than postoperative radiotherapy should be performed when possible. Future studies should evaluate the effectiveness of different approaches in treating complications considering implant survivorship free of revision for a second complication.

LEVEL OF EVIDENCE

Level III, therapeutic study.

Total femur prosthesis in oncological and not oncological series. Survival and failures

Total femur prosthesis (TFP) can be used in both oncological and prosthetic revision surgery. A retrospective analysis of 32 patients receiving a TFP at a single Center between 2002 and 2018 was performed. The average follow-up was 60 months. Revision implant free survival (RIFS) of the implants was 87% at 5 and 10 years and 72% at 15 years. Overall implant survival (OIS) of the prosthesis was 90% at 5, 10 and 15 years. Complications observed: two soft tissue failures, two infection failure and one tumor progression failure.

Functional and Surgical Outcomes After Endoprosthetic Reconstruction With Expandable Prostheses in Children: A Systematic Review

Treatment of bone sarcomas in children is associated with wide tumor re-section and segmental reconstruction. The optimal surgical approach is still under debate in the literature. During the past decade, the application of expandable prostheses has gained remarkable attention because it improves patients' appearance and allows limb growth preventing leg length discrepancy. A systematic review of the literature was performed to identify studies focusing on the functional and surgical outcomes of the application of expandable endoprostheses. [Orthopedics. 2019; 42(4):184-190.].

[Total endoprosthetic replacement of femur, humerus and tibia]

Improvements in diagnostics and effectiveness of chemotherapy have resulted in most patients with primary malignant bone tumours being candidates for limb salvage surgery. Herewith, the use of modern modular tumour endoprostheses allows for the replacement of all big joints and even entire long bones such as the femur, humerus and tibia. In this article, we focus on individual prerequisites for and challenges with performing a total endoprosthetic reconstruction of the above-mentioned anatomic structures. Additionally, data from the literature with regards to functional outcome, problems and complications are presented.

Total femur replacement in non-oncologic indications: Functional and radiological outcomes from a French survey with a mean 6 years' follow-up

INTRODUCTION

There are few published studies on total femur replacement (TFR) because its indications are rare. Other than malignant diseases, the indications extend to revisions and interprosthetic femur fractures; however, the outcomes of these indications have not been well defined. The aim of this retrospective survey was to analyze the complication rate and functional outcomes of these newer indications.

HYPOTHESIS

The morbidity and outcomes after TFR are comparable to those reported in the literature for non-cancer indications.

MATERIAL AND METHODS

Between 1997 and 2016, 29 TFR procedures were done at 6 French teaching hospitals in 15 women and 14 men, average age 68±14 years [32-85]. The primary indication was degenerative joint disease in the hip and/or knee in 16 cases, mechanical failure of the implant used after tumor resection in 11 cases and femur fracture in 2 cases. The mean number of surgical procedures before TFR was 3.6 (maximum 5) at the hip and 4.5 (maximum 10) at the knee. Six different models were implanted consisting of a rotational hinge knee (except in one case); 20 patients received a dual mobility system and 9 a standard hip replacement bearing. The femoral shaft was partially conserved 21/29 times and the trochanter 25/29 times.

RESULTS

Five patients suffered a general complication and 12 suffered a local complication (including 4 hematomas and 2 hip dislocations). Eight patients (28.6%) suffered a surgical site infection, although three had a prior infection. Among the 12 patients with a history of infection or progressive infection before the TFR, 9 healed and 3 had the infection continue. At a minimum follow-up of 2 years and mean of 6 years, 23 TFR implants were still in place and not infected; the other 6 had been removed or were infected, including one patient who underwent disarticulation. The median survival of the non-infected TFR was 15 years. At 10 years, 70% of TFR implants were still in place and non-infected. Walking was possible with or without a cane in 15 patients (51.7%), with two canes or a walker in 12 patients (41.3%) and impossible in 2 patients. Active knee flexion averaged 79.4°±30.3° [0°-120°]; 17 patients (62.9%) had 90° or more flexion; two patients (7.4%) had no flexion. The extension deficit averaged 3.7°±7°[-20° to 10°] and 20 patients had no flexion deformity. The leg length difference averaged 1.3cm±2.3 [0-10]; 19 patients (67.8%) had no difference in leg length.

DISCUSSION

Our starting hypothesis was confirmed for the complication rate and clinical outcomes. The benefits of dual mobility cups are emphasized. While the indications for TFR are rare, they will likely increase in the coming years.

LEVEL OF EVIDENCE

IV, Retrospective cohort study….

Mechanisms of failure and survival of total femoral endoprosthetic replacements

AIMS

The aim of this study was to evaluate the prosthesis characteristics and associated conditions that may modify the survival of total femoral endoprosthetic replacements (TFEPR).

PATIENTS AND METHODS

In all, 81 patients treated with TFEPR from 1976 to 2017 were retrospectively evaluated and failures were categorized according to the Henderson classification. There were 38 female patients (47%) and 43 male patients (53%) with a mean age at diagnosis of 43 years (12 to 86). The mean follow-up time was 10.3 years (0 to 31.7). A survival analysis was performed followed by univariate and multivariate Cox regression to identify independent implant survival factors.

RESULTS

The revision-free survival of the implant was 71% at five years and 63.3% at ten years. Three prostheses reached 15 years without revision. The mean Musculoskeletal Tumor Society score in the group was 26 (23 to 28). The mechanisms of failure were infection in 18%, structural failures in 6%, tumour progression in 5%, aseptic loosening in 2%, and soft-tissue failures in 1%. Prostheses used for primary reconstruction after oncological resections had lower infection rates than revision implants (8% vs 25%; p = 0.001). The rates of infection in silver-coated and non-silver-coated prosthesis were similar (17.4% vs 19.%; p = 0.869). The incidence of hip dislocation was 10%. Rotating hinge prosthesis had a lower failure rate than fixed hinge prosthesis (5.3% vs 11%). After Cox regression, the independent factors associated with failures were the history of previous operations (hazard ratio (HR) 3.7; p = 0.041), and the associated arthroplasty of the proximal tibia (HR 3.8; p = 0.034). At last follow-up, 11 patients (13%) required amputation.

CONCLUSION

TFEPR offers a reliable reconstruction option for massive bone loss of the femur, with a good survival when the prosthesis is used as a primary implant. The use of a rotating hinge at the knee and dual mobility bearing at the hip may be adequate to reduce the risk of mechanical and soft-tissue failures. Infection remains the main concern and there is insufficient evidence to support the routine use of silver-coated endoprosthesis. Cite this article: Bone Joint J 2019;101-B:522-528.

Comparison of minimally invasive and non-invasive systems in lengthening total femoral prostheses

Aims

The aim of this study was to describe, analyze, and compare the survival, functional outcome, and complications of minimally invasive (MI) and non-invasive (NI) lengthening total femoral prostheses.

Patients and Methods

A total of 24 lengthening total femoral prostheses, 11 MI and 13 NI, were implanted between 1991 and 2016. The characteristics, complications, and functional results were recorded. There were ten female patients and ten male patients. Their mean age at the time of surgery was 11 years (2 to 41). The mean follow-up was 13.2 years (seven months to 29.25 years). A survival analysis was performed, and the failures were classified according to the Modified Henderson System.

Results

The overall implant survival was 79% at five, ten, and 20 years for MI prostheses, and 84% at five years and 70% at ten years for NI prostheses. At the final follow-up, 13 prostheses did not require further surgery. The overall complication rate was 46%. The mean revision-free implant survival for MI and NI prostheses was 59 months and 49 months, respectively. There were no statistically significant differences in the overall implant survival, revision-free survival, or the distribution of complications between the two types of prosthesis. Infection rates were also comparable in the groups (9% vs 7%; p = 0.902). The rate of leg-length discrepancy was 54% in MI prostheses and 23% in NI prostheses. In those with a MI prosthesis, there was a smaller mean range of movement of the knee (0° to 62° vs 0° to 83°; p = 0.047), the flexion contracture took a longer mean time to resolve after lengthening (3.3 months vs 1.07 months; p < 0.001) and there was a lower mean Musculoskeletal Tumor Society (MSTS) score (24.7 vs 27; p = 0.295).

Conclusion

The survival and complications of MI and NI lengthening total femoral prostheses are comparable. However, patients with NI prosthesis have more accurate correction of leg-length discrepancy, a better range of movement of the knee and an improved overall function.

[Advances in total femur replacement]

Objective

To summarize the advances of total femur replacement in recent years.

Methods

The literature related to total femur replacement was reviewed, and the indications, techniques, prosthesis design, complications, rehabilitation, and function were summarized.

Results

The indication of total femur replacement is a wide involvement of the femur, skip lesions and a huge bone defect in revision. Watson-Jone is the main incision in the proximal, and then the full length of the thigh to the patella. Vascular and nerve bundle, abduction muscles are well protected, and combined or costumed prosthesis are replaced. The prosthesis design progresses, showing a diversified prostheses. Complication is frequent and varied. Rehabilitation in early stage is physical therapy, weight training is evolutionary. The main function evaluation system is Musculoskeletal Tumor Society (MSTS) score.

Conclusion

Total femur replacement is effective in limb salvage. Large sample size and long-term follow-up study should be carried out to unify indications and functional exercise standards and reduce postoperative complications.

Individualized reconstruction for severe periprosthetic fractures around the tumor prosthesis of knee under assistance of 3D printing technology: A case report

INTRODUCTION

Periprosthetic femoral fractures (PFF) around tumor prosthesis of knee are stubborn problems for surgeons, huge bone defect and inappropriate biomechanics of the revision implant design can be disaster for reconstruction. With the development of three-dimensional (3D) printing technology, surgeons participate more in precise preoperative design and simulation for treatment of such fractures. In this study we explored an accurate and feasible way to restore normal anatomy and function of the knee joint with 3D printing technology.

CASE PRESENTATION

Rationale: This report explored an accurate and feasible way to treat PFF around tumor knee prosthesis in a 32 years old women with 3D printing technology, which restored normal anatomy and function of the knee joint. Patient concerns: Pain in left thigh lasted for 10 months after resection of left femoral chondroma and knee joint replacement four years ago. Diagnoses: periprosthetic femoral fractures (PFF) around tumor knee prosthesis.

INTERVENTIONS

CT images of the patient were collected and reconstructed. Parameters of bilateral femurs were virtually sliced and measured. Novel femoral stem and nail paths were specially designed by doctors according to these parameters. The prosthetic femoral stem components and navigator were customized by engineers according to the doctor's design. The residual femoral resin model, customized components and navigator were printed with Stereo Lithography Apparatus 3D printer. The shape-preconcerted allograft bone was selected as patch for the bone defect before operation with the printed bone model. All the steps were simulated preoperatively with the models printed, and then the operation was carried out.

OUTCOMES

The operation was successfully performed. The postoperative x-ray image, MSTS93 scores were examined and the function restoration sustained well in the follow-up period from 1 month to 27 months.

LESSONS

3D printing and medical interaction are key points in complex PFF cases.

CONCLUSION

As for PFF of the complex tumor of knee, preoperative design and simulation with 3D printing technology may provide more accurate and effective operative outcome than traditional methods, which might be considered as a method suitable for popularization in complex and severe cases.

Is Total Femur Replacement a Reliable Treatment Option for Patients With Metastatic Carcinoma of the Femur?

BACKGROUND

The majority of metastatic bone lesions to the femoral bone can be treated without surgery or with minimally invasive intramedullary nailing. In rare patients with extensive metastatic disease to the femur, total femur replacement may be the only surgical alternative to amputation; however, little is known about this approach.

QUESTIONS/PURPOSES

In a highly selected small group of patients with metastatic carcinoma of the femur, we asked: (1) What was the patient survivorship after this treatment? (2) What was the implant survivorship free from all-cause revision and amputation, and what complications were associated with this treatment? (3) What functional outcomes were achieved by patients after total femur replacement for this indication?

METHODS

Eleven patients (three men, eight women) with a mean age of 64 years (range, 41-78 years) received total femur replacements between 1986 and 2016; none were lost to followup. The most common primary disease was breast cancer. In general, during this period, our indications for this procedure were extensive metastatic disease precluding internal fixation or isolated proximal or distal femur replacement, and an anticipated lifespan exceeding 6 months. Our contraindication for this procedure during this time was expected lifespan less than 6 months. Patient survival was assessed by Kaplan-Meier analysis; implant survival free from revision surgery and amputation were assessed by competing risk analysis. Function was determined preoperatively and 6 to 12 weeks postoperatively with the Musculoskeletal Tumor Society (MSTS) score normalized to a 100-point scale, with higher scores representing better function from a longitudinally maintained institutional database.

RESULTS

Eleven patients died at a median of 5 months (range, 1-31 months) after surgery. One-year revision-free and limb survival were 82% (95% CI, 51%-98%) and 91% (95% CI, 61%-99%), respectively. Reasons for reoperation were hip dislocation, infection and local recurrence in one patient each. The latter two complications resulted in amputation in two patients. The median MSTS score was 32 (range, 13-57).

CONCLUSIONS

Despite attempts to select patients who might have anticipated greater life expectancy, eight of 11 patients died by 6 months after surgery, and an additional two patients had undergone an amputation at 8 and at 17 months postoperatively. Most patients undergoing total femur replacement in this series did not recover from the procedure by the time they died, despite our best attempts to perform the procedure in patients whom we thought would live at least 6 months. Based on this, we believe that most patients with extensive metastatic disease to the femur should be offered palliative care, rather than major reconstruction.

LEVEL OF EVIDENCE

Level IV, therapeutic study.

Use of an Artificial Ligament Decreases Hip Dislocation and Improves Limb Function After Total Femoral Prosthetic Replacement Following Femoral Tumor Resection

BACKGROUND

Hip dislocation is a major complication of total femoral prosthetic reconstruction (TFR) after femoral tumor resection. Hip dislocation can occur because of inadequate functional abductor musculature, inadequate hip capsule repair, or a long lever arm after total femur replacement. To eliminate the negative effects of these factors on the risk of hip dislocation, the use of artificial ligaments may help to increase the stability of the hip joint. We aimed to determine whether application of an artificial ligament would improve limb function and active range of movement (ROM) after TFR.

METHODS

Fifty-eight patients who underwent femoral tumor resection and TFR were included. A band-shaped artificial ligament was wrapped spirally around the proximal site of the total femur prosthesis for periacetabular soft tissue reconstruction in 12 patients. The other 46 patients did not consent to receiving the artificial ligament. Complications including hip dislocation and infection, limb function, and active hip ROM were compared between patients who did and did not receive the artificial ligament.

RESULTS

The hip dislocation rate was lower in the patients who received the artificial ligament. The risk of deep infection did not differ between groups. The group that received the ligament also achieved better limb function and active ROM on flexion and abduction.

CONCLUSION

Patients treated with total femur resection and endoprosthetic replacement with an artificial ligament for periacetabular soft tissue reconstruction had a more stable hip joint, better limb function, and greater active hip ROM than did patients who did not receive an artificial ligament.

Is total femoral replacement for non-oncologic and oncologic indications a safe procedure in limb preservation surgery? A single center experience of 22 cases

Background

Several surgical options for the reconstruction of massive bone defects have been described and include biologic methods with autografts and allografts, and the use of tumor endoprostheses (total femoral replacement, TFR). Several types of modular TFR are available, but nevertheless unpredictable outcomes and high complication rates have been described from most authors. The present study aims to compare results after TFR performed with modular total femur prosthesis MML (Fa. ESKA/Orthodynamics) in patients with and without malignant disease.

Methods

Retrospective chart review and functional investigation (Musculoskeletal Tumor Society (MSTS) score, Harris Hip Score (HHS), Oxford Knee Score (OKS), SF-12 Health Survey, and failure classification according to Henderson) of TFR cases from 1995 to 2011. Indications for TFR were malignant tumor resection from the femur (n = 9, Group A) or failure of a revision arthroplasty without history of malignant disease (n = 13, Group B).

Results

Thirty-six patients were treated during the study period, of whom 22 could be investigated clinically after a mean follow-up of 63 months. Overall failure rate for TFR was 59.1%, leading to 38 surgical revisions. The most common failure mechanisms were Type I (soft tissue), followed by Type IV (infection) and Type III (mechanical failure). Mean MSTS score out of 30 was 13 (range 1–25), with significantly higher scores in Group A (mean 19, range 3–25) than Group B (mean 9, range 1–15).

Conclusion

TFR is an established procedure to restore femoral integrity. However, complication rates are considerably high, and depend mainly on the age at initial reconstruction.

Osteogenesis induced by a three-dimensional bioimplant composed of demineralised bone matrix, collagen, hydroxyapatite, and bone marrow-derived cells in massive bone defects: An experimental study

Treatment of massive bone defects is one of the most difficult problems to solve in orthopedics. At present, there is no consensus on the best way to resolve these problems. The aim of our study was to evaluate the effect of a three-dimensional bioimplant over massive bone defects, and to analyse if it improves the speed and quality of integration in recipient bone compared to allograft treatment. Fifteen female lambs with massive bone defects, surgically created in their tibias, were randomly divided into three groups of five lambs each: Group I -treated with the bioimplant; Group 2 -treated with the bioimplant plus nucleated cells of autologous bone marrow; Group 3 -treated with a frozen allograft. Radiographs were taken post-treatment at weeks 1, 6, and 12. Animals were euthanized to obtain the studied bone segment for morphological analyses.

TREATMENT

with bioimplants vs. bioimplant plus bone marrow nucleated cells (BMNCs) showed a notorious osteogenic effect, but with greater osteoid synthesis and cellularity in the latter. These results suggest that combined treatment with bioimplants and BMNCs have an additive effect on massive bone defects in lambs. These experimental results could be applied to repair damaged human bone.

Long-term outcomes of cement in cement technique for revision endoprosthesis surgery

BACKGROUND AND OBJECTIVE

Cemented endoprosthetic reconstruction after resection of primary bone sarcomas has been a standard-of-care option for decades. With increased patient survival, the incidence of failed endoprostheses requiring revision surgery has increased. Revision of cemented endoprotheses by cementing into the existing cement mantle (CiC) is technically demanding.

METHODS

This is a retrospective review of our endoprosthesis database of 512 consecutive cemented endoprosthetic reconstructions performed for oncologic diagnoses between 1980 and 2014. A total of 54 implants (mean patient age 32 years, range 13-81) were revised with a CiC technique. Outcomes evaluated were prosthesis survival, revision surgery categorized according to the Henderson Failure Mode Classification, complications, and functional scores.

RESULTS

Fifteen-year Kaplan-Meier survival rate was 34% for initial revision and 39% for subsequent revision implants. Mean revised Musculoskeletal Tumor Society (MSTS) Score was 27 at latest follow-up. Infection rate was 2%, 9%, and 13% for primary endoprostheses, initial revisions, and subsequent revisions, respectively. Limb salvage rate was 87%.

CONCLUSIONS

At long-term follow up, endoprostheses revised with the CiC technique showed consistent 15-year survival from initial (34%) to subsequent (39%) revision. Despite a relatively high failure rate, these results are encouraging and demonstrate that this is a conservative, repeatable technique.

Silver-coated modular Megaendoprostheses in salvage revision arthroplasty after periimplant infection with extensive bone loss - a pilot study of 34 patients

Background

Hip and knee replacements in patients with bone defects after infection correlates with high rates of reinfection. In this vulnerable patient population, the prevention of reinfection is to be considered superordinate to the functionality and defect bridging. The use of silver coating of aseptic implants as an infection prophylaxis is already proven; however, the significance of these coatings in septic reimplantation of large implants is still not sufficiently investigated.

Methods

In a retrospective analysis, 34 patients who have been treated with a modular mega-endoprosthesis after a cured bone infection of the lower limb (femur or tibia) have been evaluated. One group with 14 patients (NSCG: non silver- coated group) was supplied with the non silver- coated implants: MML München- Lübeck™ modular endoprosthesis system (AQ Implants, Ahrensburg, Germany) or MUTARS® Modular Universal Tumor And Revision System (Implantcast GmbH, Buxtehude, Germany). The other group with 20 patients (SCG: silver- coated group) was supplied with the silver- coated system of MUTARS®. In addition to the clinical findings and the patients’ histories, specifically the reinfection rates, the patients’ mobility was assessed using the New Mobility Score (NMS, by Parker and Palmer).

Results

The median follow-up period was 72 months, ranging from 6 to 267 months. The dropout rate was 5.8%. The reinfection rate after healed reinfection in SCG was 40% (8/20), in NSCG 57% (8/14), p = 0.34; α =0.05. The time for reinfection was, on average, 14 months (1–72 months) in SCG and 8 months (1–48 months) in the NSCG (p = 0.61; α =0.05). The two groups showed no differences in the NMS.

Conclusion

With this retrospective analysis, it can be determined that the rate of reinfection of modular mega-endoprostheses on the hip and knee joint after healed periprosthetic joint infection (PJI) can be reduced by the use of silver coated implants. The time until reinfection can also be delayed by utilizing silver coated implants. Due to the low number of cases of this highly specific patient population, no statistical significance could be determined. A positive effect, however, can be assumed through the use of silver coatings in mega-endoprostheses after an infectious situation.

Sonication culture improves microbiological diagnosis of modular megaprostheses

Modular megaprostheses are known for high infection rates followed by high rates of revisions. Microbial biofilms growing adherently on prosthetic surfaces may inhibit the detection of the pathogens causing prosthetic joint infections. We sought to answer the following questions: Does sonication culture (SC) improve the microbiological diagnosis of periprosthetic infections of megaprostheses compared to conventional tissue culture (TC)? Which pathogens were detected on the surface of megaprostheses with either SC or TC and do the findings help to identify low-grade infections? Included were 31 patients with modular megaprostheses, whose implant had been explanted due to suspected joint infection or revision surgery. SCs were performed according to the protocol by Trampuz et al. The diagnosis of infection was evaluated according to the definition of the Musculoskeletal Infection Society. The sensitivity of SC was 91.3% compared to 52.2% for TC and the specificity was 100% for SC and TC (p = 0.004). Under preoperative antibiotic therapy, the sensitivity of SC was 83.3% while the sensitivity of TC was 50%. Without preoperative antibiotic therapy the sensitivity of SC was 100% compared to 54.5% for TC. In nine cases, SCs detected microorganisms, while TC was negative. Detected bacteria were Staphylococcus epidermidis in four, Micrococcus species in one, Finegoldia magna in one, Brevibacterium casei in one, Pseudomonas fluorescens in one, and Enterococcus faecium in one. SC is a reliable method for dislodging pathogens from orthopedic implants. The SC of modular megaprostheses showed significantly higher pathogen detection than the periprosthetic TC, especially for low virulence pathogens. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:1383-1387, 2017.

The Significance of Rectus Femoris for the Favorable Functional Outcome After Total Femur Replacement

Background:

In treatment of tumors, we usually reconstruct after resection of the entire femur using only metallic modular endoprostheses among many procedures and defined it as a total femur replacement. We studied the interrelation between the preservation of rectus femoris and the functional outcome after total femur replacement.

Methods:

We rated the functional outcomes of 21 patients who underwent total femur replacement. We categorized the subjects into 2 groups: group A (rectus femoris preserved) and group B (rectus femoris unpreserved). We examined them based on the Mann-Whitney U test between the 2 groups in average through the Musculoskeletal Tumor Society functional scores.

Results:

The average score of group A was 20 of 25 (11–25; 80%), whereas the average score of group B was 10 of 25 (4–13; 40%). There was significant difference between the groups (P = 0.00168877).

Conclusion:

We found that the preservation of rectus femoris is imperative for achieving the favorable functional outcome in total femur replacement.

Periprosthetic joint infections in modular endoprostheses of the lower extremities: a retrospective observational study in 101 patients

Background

Modular mega-endoprosthesis systems are used to bridge very large bone defects and have become a widespread method in orthopaedic surgery for the treatment of tumours and revision arthroplasty. However, the indications for the use of modular mega-endoprostheses must be carefully considered. Implanting modular endoprostheses requires major, complication-prone surgery in which the limited salvage procedures should always be borne in mind. The management of periprosthetic infection is particularly difficult and beset with problems.

Given this, the present study was designed to gauge the significance of periprosthetic infections in connection with modular mega-implants in the lower extremities among our own patients.

Methods

Patients who had been fitted with modular endoprosthesis on a lower extremity at our department between September 1994 and December 2011 were examined retrospectively. A total of 101 patients with 114 modular prostheses were identified. Comprising 30 men (29.7 %) and 71 women (70.3 %), their average age at the time of surgery was 67 years (18–92 years).

Results

The average follow-up period was 27 months (5 months and 2 weeks to 14 years and 11 months) and the drop-out rate was about 8.8 %. Altogether, there were 19 (17.7 %) endoprosthesis infections: 3 early infections and 16 late or delayed infections. The pathogen spectrum was dominated by coagulase-negative staphylococci (36 %) and Staphylococcus aureus (16 %), including 26 % multi-resistant pathogens. Reinfection occurred in 37 % of cases of infection. Tumours were followed by significantly fewer infections than the other indications. Infections were twice as likely to occur after previous surgery.

Conclusion

In our findings modular endoprostheses (18 %) are much more susceptible to infection than primary endoprostheses (0.5–2,5 %). Infection is the most common complication alongside the dislocation of proximal femur endoprostheses. Consistent, radical surgery is essential – although even with an adequate treatment strategy, the recurrence rate is very high. Unfortunately, the functional results are frequently unsatisfactory, with amputation often being the last resort. Therefore, the indication for implantation must be carefully considered and discussed in great detail, especially in the case of multimorbid patients with previous joint infections.