LUMiC Endoprosthetic Reconstruction of Periacetabular Tumor Defects: A Multicenter Follow-up Study.

BACKGROUND: We previously reported promising early results for periacetabular tumor reconstructions using the LUMiC prosthesis. The current study evaluates mid-term complications, revision rates, cumulative incidence of implant revision, and risk factors for complications in a multicenter cohort. METHODS: We assessed patients in whom a tumor defect after type P1b+2, P2, P2+3, or P1b+2+3 internal hemipelvectomy was reconstructed with a LUMiC prosthesis during the period of 2008 to 2022. Complications were reported according to the Henderson classification. Competing risks models were used to estimate the cumulative incidence of implant revision for mechanical and nonmechanical reasons, and reoperations for any complication. Cox models were used to study the effect of risk factors on dislocation and infection. RESULTS: One hundred and sixty-six patients (median follow-up, 4.2 years [interquartile range, 2.6 to 7.6 years]) were included. A total of 114 (69%) were treated for a primary malignant tumor, 46 (28%) for metastatic carcinoma, 5 (3%) for a benign aggressive lesion, and 1 (1%) for another reason. One hundred and sixty-five reoperations were performed in 82 (49%) of the patients; 104 (63%) of the reoperations were within 6 months. Thirty-two (19%) of 166 implants were revised: 13 (8%) for mechanical reasons, mainly dislocation (n = 5, 3%), and 19 (11%) for nonmechanical reasons, mainly periprosthetic joint infection (PJI) (n = 15, 9%). The cumulative incidences of revision for mechanical reasons and PJI (Henderson 1 to 4) at 2, 5, and 10 years were 11% (95% confidence interval [CI], 7% to 17%), 18% (12% to 25%), and 24% (16% to 33%), respectively. Previous surgery at the same site was associated with an increased dislocation risk (cause-specific hazard ratio [HRCS], 3.0 [95% CI, 1.5 to 6.4]; p < 0.01), and resections involving the P3 region were associated with an increased infection risk (HRCS, 2.5 [95% CI, 1.4 to 4.7]; p < 0.01). CONCLUSIONS: Despite a substantial reoperation risk, the LUMiC prosthesis demonstrated its durability in the mid-term, with a low mechanical revision rate and most patients retaining their primary implant. Most complications occur in the first postoperative months. Patients with previous surgery at the same site had an increased dislocation risk and might benefit from more conservative rehabilitation and aftercare. Measures should be aimed at reducing the PJI risk, especially in resections involving the P3 region. LEVEL OF EVIDENCE: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Inhaled Corticosteroids, Vitamin K Antagonists and Amlodipine Were Associated with an Increased Risk of Acute Periprosthetic Joint Infection in Patients with Total Hip Arthroplasty: A Retrospective Case-Cohort Study.

The perioperative use of certain medication may influence the risk of developing a periprosthetic joint infection (PJI). Inhaled corticosteroids (ICSs) and cardiovascular drugs are widely used against pulmonary and cardiovascular diseases. While oral corticosteroids and anticoagulants have been shown to increase the risk of developing PJI, this is not clear for ICSs. In contrast, some cardiovascular drugs, such as amlodipine, nifedipine and statins, have been documented to show an antimicrobial effect, suggesting a synergistic effect with antibiotics in the treatment of (multi-resistant) microorganisms. We performed a case-cohort study to assess the association between the occurrence of PJI after THA and the use of inhaled corticosteroids, anticoagulants, or previously mentioned cardiovascular agents. In a cohort of 5512 primary THAs, we identified 75 patients with a PJI (1.4%), and randomly selected 302 controls. A weighted Cox proportional hazard regression model was used for the study design and to adjust for potential confounders (age, sex, smoking, and cardiovascular/pulmonary disease). We found ICS use (HR 2.6 [95% CI 1.1-5.9]), vitamin K antagonist use (HR 5.3 [95% CI 2.5-11]), and amlodipine use (HR 3.1 [95% CI 1.4-6.9]) to be associated with an increased risk of developing PJI after THA. The effect remained after correction for the mentioned possible confounders. The underlying diseases for which the medications are prescribed could also play a role in the mentioned association; we believe, however, that the usages of ICSs, vitamin K antagonists and amlodipine appear to be potential modifiable risk factors for PJI, and therefore have to be questioned during preoperative screening and consultation.

A new three-step hybrid approach is a safe procedure for incisional hernia: early experiences with a single centre retrospective cohort.

PURPOSE: In this study, a three-step novel surgical technique was developed for incisional hernia, in which a laparoscopic procedure with a mini-laparotomy is combined: so-called 'three-step incisional hybrid repair'. The aim of this study was to reduce the risk of intestinal lacerations during adhesiolysis and recurrence rate by better symmetrical overlap placement of the mesh. OBJECTIVES: To evaluate first perioperative outcomes with this technique. METHODS: From 2016 to 2020, 70 patients (65.7% females) with an incisional hernia of > 2 and ≤ 10 cm underwent a elective three-step incisional hybrid repair in two non-academic hospitals performed by two surgeons specialised in abdominal wall surgery. Intra- and postoperative complications, operation time, hospitalisation time and hernia recurrence were assessed. RESULTS: Mean operation time was 100 min. Mean hernia size was 4.8 cm; 45 patients (64.3%) had a hernia of 1-5 cm, 25 patients (35.7%) of 6-10 cm. Eight patients had a grade 1 complication (11.4%), five patients a grade 2 (7.1%), two patients (2.8%) a grade 4 complication and one patient (1.4%) a grade 5 complication. Five patients had an intraoperative complication (7.0%), two enterotomies, one serosa injury, one omentum bleeding and one laceration of an epigastric vessel. Mean length of stay was 3.3 days. Four patients (5.6%) developed a hernia recurrence during a mean follow-up of 19.5 weeks. CONCLUSION: A three-step hybrid incisional hernia repair is a safe alternative for incisional hernia repair. Intraoperative complications rate was low.

Laparoscopic Repair with Mesh Reinforcement is a Feasible Alternative for Epigastric Hernia: A Retrospective Study Comparing Laparoscopic with Open Repair.

BACKGROUND: Epigastric hernias may lead to discomfort and pain. The mainstay of treatment is surgical repair with mesh reinforcement. The primary aim of this study was to compare the recurrence rates of laparoscopic epigastric hernia repair (LEHR) and conventional open epigastric hernia repair (OEHR) with mesh reinforcement. Secondary aims were to evaluate perioperative outcomes and quality of life. METHODS: Ninety-nine patients (58% female) from two non-academic hospitals were retrospectively reviewed. The Short-Form 36 Health Survey questionnaire and Carolina Comfort Scale were used to assess quality of life and complaints related to mesh implantation. RESULTS: Forty-two (42%) patients underwent LEHR and 57 (58%) underwent OEHR. The mean follow-up at the outpatient clinic was 7.1 months in the LEHR group and 8.1 months in the OEHR group. The mean follow-up by telephone contact was 67.8 months in the OEHR group and 58.1 months in the LEHR group. The risk of recurrence appeared to be slightly lower for LEHR (2%) compared to OEHR (7%), but this difference was not significant (p=0.298). The median surgical duration was 54 minutes in the LEHR group and 28 minutes in the OEHR group (p<0.001). The median hospitalization time was 1 day in the LEHR group and 0.5 days in the OEHR group (p<0.001). CONCLUSION: Laparoscopic hernia repair tended to be associated with a lower risk of recurrence, but this difference was not statistically significant. Although the surgical duration was longer for the LEHR group, the postoperative outcomes were similar between groups, making laparoscopic repair a feasible alternative to the open approach for epigastric hernias.

Conventional Primary Central Chondrosarcoma of the Pelvis: Prognostic Factors and Outcome of Surgical Treatment in 162 Patients.

BACKGROUND: Studies focusing on the oncological outcome after treatment of conventional primary central chondrosarcoma of pelvic bone are lacking. We conducted this retrospective study at 5 referral centers to gain insight in the outcome of treatment for this tumor type and to identify risk factors for impaired oncological outcome. METHODS: One hundred and sixty-two consecutive patients (118 male patients [73%]) who underwent resection of a conventional primary central chondrosarcoma of pelvic bone from 1985 to 2013 were evaluated. The median age was 51 years (range, 15 to 78 years). The median follow-up was 12.6 years (95% confidence interval [CI], 8.4 to 16.9 years). There were 30 grade-I lesions (19%), 93 grade-II lesions (57%), and 39 grade-III lesions (24%). RESULTS: Sixty-two patients (38%) experienced local recurrence: 9 grade-I lesions (30%), 31 grade-II lesions (33%), and 22 grade-III lesions (56%). Forty-eight patients (30%) developed metastases. The risk of disease-related death was 3% for grade-I tumors (1 of 30; this patient had a grade-II recurrence and died of metastases), 33% (31 of 93) for grade-II tumors, and 54% (21 of 39) for grade-III tumors. Identified risk factors for impaired disease-specific survival were tumor grade (grade II: hazard ratio [HR], 20.18; p = 0.003; and grade III: HR, 58.94; p < 0.001), resection margins (marginal: HR, 3.21; p = 0.001; and intralesional: HR, 3.56; p < 0.001), and maximal tumor size (HR, 1.08 per cm; p = 0.026). Deep infection (19% [n = 31]) was the predominant complication. CONCLUSIONS: This study offers a standard for survival rates for conventional primary central chondrosarcoma of the pelvis. The survival for grade-I tumors was excellent. Wide resection margins were associated with a significant survival advantage for higher-grade tumors. Because of the inability to reliably distinguish low-grade and high-grade tumors preoperatively, we conclude that any central pelvic chondrosarcoma should be treated with aggressive primary resection with the aim of obtaining wide resection margins. There may be aggressive biologic features in some tumors for which a surgical procedure alone may not be adequate to improve outcomes. LEVEL OF EVIDENCE: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

LUMiC® Endoprosthetic Reconstruction After Periacetabular Tumor Resection: Short-term Results.

BACKGROUND: Reconstruction of periacetabular defects after pelvic tumor resection ranks among the most challenging procedures in orthopaedic oncology, and reconstructive techniques are generally associated with dissatisfying mechanical and nonmechanical complication rates. In an attempt to reduce the risk of dislocation, aseptic loosening, and infection, we introduced the LUMiC® prosthesis (implantcast, Buxtehude, Germany) in 2008. The LUMiC® prosthesis is a modular device, built of a separate stem (hydroxyapatite-coated uncemented or cemented) and acetabular cup. The stem and cup are available in different sizes (the latter of which is also available with silver coating for infection prevention) and are equipped with sawteeth at the junction to allow for rotational adjustment of cup position after implantation of the stem. Whether this implant indeed is durable at short-term followup has not been evaluated. QUESTIONS/PURPOSES: (1) What proportion of patients experience mechanical complications and what are the associated risk factors of periacetabular reconstruction with the LUMiC® after pelvic tumor resection? (2) What proportion of patients experience nonmechanical complications and what are the associated risk factors of periacetabular reconstruction with the LUMiC® after pelvic tumor resection? (3) What is the cumulative incidence of implant failure at 2 and 5 years and what are the mechanisms of reconstruction failure? (4) What is the functional outcome as assessed by Musculoskeletal Tumor Society (MSTS) score at final followup? METHODS: We performed a retrospective chart review of every patient in whom a LUMiC® prosthesis was used to reconstruct a periacetabular defect after internal hemipelvectomy for a pelvic tumor from July 2008 to June 2014 in eight centers of orthopaedic oncology with a minimum followup of 24 months. Forty-seven patients (26 men [55%]) with a mean age of 50 years (range, 12-78 years) were included. At review, 32 patients (68%) were alive. The reverse Kaplan-Meier method was used to calculate median followup, which was equal to 3.9 years (95% confidence interval [CI], 3.4-4.3). During the period under study, our general indications for using this implant were reconstruction of periacetabular defects after pelvic tumor resections in which the medial ilium adjacent to the sacroiliac joint was preserved; alternative treatments included hip transposition and saddle or custom-made prostheses in some of the contributing centers; these were generally used when the medial ilium was involved in the tumorous process or if the LUMiC® was not yet available in the specific country at that time. Conventional chondrosarcoma was the predominant diagnosis (n = 22 [47%]); five patients (11%) had osseous metastases of a distant carcinoma and three (6%) had multiple myeloma. Uncemented fixation (n = 43 [91%]) was preferred. Dual-mobility cups (n = 24 [51%]) were mainly used in case of a higher presumed risk of dislocation in the early period of our study; later, dual-mobility cups became the standard for the majority of the reconstructions. Silver-coated acetabular cups were used in 29 reconstructions (62%); because only the largest cup size was available with silver coating, its use depended on the cup size that was chosen. We used a competing risk model to estimate the cumulative incidence of implant failure. RESULTS: Six patients (13%) had a single dislocation; four (9%) had recurrent dislocations. The risk of dislocation was lower in reconstructions with a dual-mobility cup (one of 24 [4%]) than in those without (nine of 23 [39%]) (hazard ratio, 0.11; 95% CI, 0.01-0.89; p = 0.038). Three patients (6%; one with a preceding structural allograft reconstruction, one with poor initial fixation as a result of an intraoperative fracture, and one with a cemented stem) had loosening and underwent revision. Infections occurred in 13 reconstructions (28%). Median duration of surgery was 6.5 hours (range, 4.0-13.6 hours) for patients with an infection and 5.3 hours (range, 2.8-9.9 hours) for those without (p = 0.060); blood loss was 2.3 L (range, 0.8-8.2 L) for patients with an infection and 1.5 L (range, 0.4-3.8 L) for those without (p = 0.039). The cumulative incidences of implant failure at 2 and 5 years were 2.1% (95% CI, 0-6.3) and 17.3% (95% CI, 0.7-33.9) for mechanical reasons and 6.4% (95% CI, 0-13.4) and 9.2% (95% CI, 0.5-17.9) for infection, respectively. Reasons for reconstruction failure were instability (n = 1 [2%]), loosening (n = 3 [6%]), and infection (n = 4 [9%]). Mean MSTS functional outcome score at followup was 70% (range, 33%-93%). CONCLUSIONS: At short-term followup, the LUMiC® prosthesis demonstrated a low frequency of mechanical complications and failure when used to reconstruct the acetabulum in patients who underwent major pelvic tumor resections, and we believe this is a useful reconstruction for periacetabular resections for tumor or failed prior reconstructions. Still, infection and dislocation are relatively common after these complex reconstructions. Dual-mobility articulation in our experience is associated with a lower risk of dislocation. Future, larger studies will need to further control for factors such as dual-mobility articulation and silver coating. We will continue to follow our patients over the longer term to ascertain the role of this implant in this setting. LEVEL OF EVIDENCE: Level IV, therapeutic study.

What Are the Long-term Results of MUTARS® Modular Endoprostheses for Reconstruction of Tumor Resection of the Distal Femur and Proximal Tibia?

BACKGROUND: Modular endoprostheses are commonly used to reconstruct defects of the distal femur and proximal tibia after bone tumor resection. Because limb salvage surgery for bone sarcomas is relatively new, becoming more frequently used since the 1980s, studies focusing on the long-term results of such prostheses in treatment of primary tumors are scarce. QUESTIONS/PURPOSES: (1) What proportion of patients experience a mechanical complication with the MUTARS® modular endoprosthesis when used for tumor reconstruction around the knee, and what factors may be associated with mechanical failure? (2) What are the nonmechanical complications? (3) What are the implant failure rates at 5, 10, and 15 years? (4) How often is limb salvage achieved using this prosthesis? METHODS: Between 1995 and 2010, endoprostheses were the preferred method of reconstruction after resection of the knee in adolescents and adults in our centers. During that period, we performed 114 MUTARS® knee replacements in 105 patients; no other endoprosthetic systems were used. Four patients (four of 105 [4%]) were lost to followup, leaving 110 reconstructions in 101 patients for review. The reverse Kaplan-Meier method was used to calculate median followup, which was equal to 8.9 years (95% confidence interval [CI], 8.0-9.7). Mean age at surgery was 36 years (range, 13-82 years). Predominant diagnoses were osteosarcoma (n = 56 [55%]), leiomyosarcoma of bone (n = 10 [10%]), and chondrosarcoma (n = 9 [9%]). In the early period of our study, we routinely used uncemented uncoated implants for primary reconstructions. Later, hydroxyapatite (HA)-coated implants were the standard. Eighty-nine reconstructions (89 of 110 [81%]) were distal femoral replacements (78 uncemented [78 of 89 {88%}, 42 of which were HA-coated [42 of 78 {54%}]) and 21 (21 of 110 [19%]) were proximal tibial replacements. In 26 reconstructions (26 of 110 [24%]), the reconstruction was performed for a failed previous reconstruction. We used a competing risk model to estimate the cumulative incidence of implant failure. RESULTS: Complications of soft tissue or instability occurred in seven reconstructions (seven of 110 [6%]). With the numbers we had, for uncemented distal femoral replacements, we could not detect a difference in loosening between revision (five of 17 [29%]) and primary reconstructions (eight of 61 [13%]) (hazard ratio [HR], 1.72; 95% CI, 0.55-5.38; p = 0.354). Hydroxyapatite-coated uncemented implants had a lower risk of loosening (two of 42 [5%]) than uncoated uncemented implants (11 of 36 [31%]) (HR, 0.23; 95% CI, 0.05-1.06; p = 0.060). Structural complications occurred in 15 reconstructions (15 of 110 [14%]). Infections occurred in 14 reconstructions (14 of 110 [13%]). Ten patients had a local recurrence (10 of 101 [10%]). With failure for mechanical reasons as the endpoint, the cumulative incidences of implant failure at 5, 10, and 15 years were 16.9% (95% CI, 9.6-24.2), 20.7% (95% CI, 12.5-28.8%), and 37.9% (95% CI, 16.1-59.7), respectively. We were able to salvage some of the failures so that at followup, 90 patients (90 of 101 [89%]) had a MUTARS® in situ. CONCLUSIONS: Although no system has yet proved ideal to restore normal function and demonstrate long-term retention of the implant, MUTARS® modular endoprostheses represent a reliable long-term option for knee replacement after tumor resection, which seems to be comparable to other modular implants available to surgeons. Although the number of patients is relatively small, we could demonstrate that with this prosthesis, an uncemented HA-coated implant is useful in achieving durable fixation. LEVEL OF EVIDENCE: Level IV, therapeutic study.